class="tags" href="/tags/C.html" title=c>content_views" class="tags" href="/tags/C.html" title=c>class="markdown_views prism-tomorrow-night">

---

class="tags" href="/tags/C.html" title=c>c="https://i-blog.class="tags" href="/tags/C.html" title=c>csdnimg.class="tags" href="/tags/C.html" title=c>cn/direclass="tags" href="/tags/C.html" title=c>ct/class="tags" href="/tags/C.html" title=c>cb7f73class="tags" href="/tags/C.html" title=c>cda1a14130840e356class="tags" href="/tags/C.html" title=c>cb0b6f9e4.png#piclass="tags" href="/tags/C.html" title=c>c_class="tags" href="/tags/C.html" title=c>center" alt="在这里插入图片描述" width="100" />

<class="tags" href="/tags/C.html" title=c>center> 博客主页： [小ᶻ☡꙳ᵃⁱᵍᶜ꙳] class="tags" href="/tags/C.html" title=c>center> <class="tags" href="/tags/C.html" title=c>center> 本文专栏: C++ class="tags" href="/tags/C.html" title=c>center>

---

---

class="tags" href="/tags/C.html" title=c>c="https://img-blog.class="tags" href="/tags/C.html" title=c>csdnimg.class="tags" href="/tags/C.html" title=c>cn/direclass="tags" href="/tags/C.html" title=c>ct/00d4fdeb7b0d4dbb99e88f325ef249d8.gif#piclass="tags" href="/tags/C.html" title=c>c_class="tags" href="/tags/C.html" title=c>center" alt="在这里插入图片描述" width="1000" height="100" />

---

💯前言

• 在计算机科学中࿰class="tags" href="/tags/C.html" title=c>c;字符串处理是一个非常基础且常见的任务。本题主要围绕如何将一个句子中的每个单词反转来进行练习。这个问题不仅考察了对字符串操作的理解࿰class="tags" href="/tags/C.html" title=c>c;还涉及了不同的解决方法。在本篇文章中࿰class="tags" href="/tags/C.html" title=c>c;我们将详细探讨我自己的做法、老师提出的两种做法࿰class="tags" href="/tags/C.html" title=c>c;并深入讲解C++中 <class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code> 函数的使用࿰class="tags" href="/tags/C.html" title=c>c;最后通过对比和拓展分析这些方法的优缺点。
  C++ 参考手册
  class="tags" href="/tags/C.html" title=c>c="https://i-blog.class="tags" href="/tags/C.html" title=c>csdnimg.class="tags" href="/tags/C.html" title=c>cn/direclass="tags" href="/tags/C.html" title=c>ct/f0db7class="tags" href="/tags/C.html" title=c>c348331440fa266b3class="tags" href="/tags/C.html" title=c>c24f558694.png#piclass="tags" href="/tags/C.html" title=c>c_class="tags" href="/tags/C.html" title=c>center" alt="在这里插入图片描述" />

---

💯题目描述

B2122 单词翻转
class="tags" href="/tags/C.html" title=c>c="https://i-blog.class="tags" href="/tags/C.html" title=c>csdnimg.class="tags" href="/tags/C.html" title=c>cn/direclass="tags" href="/tags/C.html" title=c>ct/34bd93aa8d2b41728b702326fa77b288.png" alt="在这里插入图片描述" />

小明同学写单词的时候喜欢反着写࿰class="tags" href="/tags/C.html" title=c>c;比如 <class="tags" href="/tags/C.html" title=c>code>helloclass="tags" href="/tags/C.html" title=c>code> 他会写成 <class="tags" href="/tags/C.html" title=c>code>ollehclass="tags" href="/tags/C.html" title=c>code>。给出小明同学写的一个句子࿰class="tags" href="/tags/C.html" title=c>c;请你将所有的单词复原。

输入格式

共一行࿰class="tags" href="/tags/C.html" title=c>c;一个字符串表示句子࿰class="tags" href="/tags/C.html" title=c>c;单词之间以空格分隔。

输出格式

每个单词一行。

样例 #1

样例输入 #1

<class="tags" href="/tags/C.html" title=c>code>olleh dlrow
class="tags" href="/tags/C.html" title=c>code>

样例输出 #1

<class="tags" href="/tags/C.html" title=c>code>hello
world
class="tags" href="/tags/C.html" title=c>code>

💯一、我的做法

代码实现：

<class="tags" href="/tags/C.html" title=c>code class="tags" href="/tags/C.html" title=c>class="prism language-class="tags" href="/tags/C.html" title=c>cpp">class="tags" href="/tags/C.html" title=c>class="token maclass="tags" href="/tags/C.html" title=c>cro property">class="tags" href="/tags/C.html" title=c>class="token direclass="tags" href="/tags/C.html" title=c>ctive-hash">#class="tags" href="/tags/C.html" title=c>class="token direclass="tags" href="/tags/C.html" title=c>ctive keyword">inclass="tags" href="/tags/C.html" title=c>clude class="tags" href="/tags/C.html" title=c>class="token string"><iostream>
class="tags" href="/tags/C.html" title=c>class="token maclass="tags" href="/tags/C.html" title=c>cro property">class="tags" href="/tags/C.html" title=c>class="token direclass="tags" href="/tags/C.html" title=c>ctive-hash">#class="tags" href="/tags/C.html" title=c>class="token direclass="tags" href="/tags/C.html" title=c>ctive keyword">inclass="tags" href="/tags/C.html" title=c>clude class="tags" href="/tags/C.html" title=c>class="token string"><string>
class="tags" href="/tags/C.html" title=c>class="token keyword">using class="tags" href="/tags/C.html" title=c>class="token keyword">namespaclass="tags" href="/tags/C.html" title=c>ce stdclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;

class="tags" href="/tags/C.html" title=c>class="token keyword">int class="tags" href="/tags/C.html" title=c>class="token funclass="tags" href="/tags/C.html" title=c>ction">mainclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)
class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">{
    string sclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
    class="tags" href="/tags/C.html" title=c>class="token keyword">whileclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(class="tags" href="/tags/C.html" title=c>cin class="tags" href="/tags/C.html" title=c>class="token operator">>> sclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)
    class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">{
        class="tags" href="/tags/C.html" title=c>class="token keyword">forclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(class="tags" href="/tags/C.html" title=c>class="token keyword">int i class="tags" href="/tags/C.html" title=c>class="token operator">= sclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">.class="tags" href="/tags/C.html" title=c>class="token funclass="tags" href="/tags/C.html" title=c>ction">sizeclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">) class="tags" href="/tags/C.html" title=c>class="token operator">- class="tags" href="/tags/C.html" title=c>class="token number">1class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">; i class="tags" href="/tags/C.html" title=c>class="token operator">>= class="tags" href="/tags/C.html" title=c>class="token number">0class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">; iclass="tags" href="/tags/C.html" title=c>class="token operator">--class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)
        class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">{
            class="tags" href="/tags/C.html" title=c>cout class="tags" href="/tags/C.html" title=c>class="token operator"><< sclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">[iclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">]class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
        class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">}
        class="tags" href="/tags/C.html" title=c>cout class="tags" href="/tags/C.html" title=c>class="token operator"><< endlclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
    class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">}
    
    class="tags" href="/tags/C.html" title=c>class="token keyword">return class="tags" href="/tags/C.html" title=c>class="token number">0class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">}
class="tags" href="/tags/C.html" title=c>code>

代码解析

在这个实现中࿰class="tags" href="/tags/C.html" title=c>c;我选择了通过手动反转每个单词的字符来恢复正确的单词顺序。

1. 变量声明：

   • <class="tags" href="/tags/C.html" title=c>code>string s;class="tags" href="/tags/C.html" title=c>code>：声明一个字符串变量 <class="tags" href="/tags/C.html" title=c>code>sclass="tags" href="/tags/C.html" title=c>code> 用于存储从输入中读取的每个单词。

2. 读取输入：

   • <class="tags" href="/tags/C.html" title=c>code>while(class="tags" href="/tags/C.html" title=c>cin >> s)class="tags" href="/tags/C.html" title=c>code>：使用 <class="tags" href="/tags/C.html" title=c>code>class="tags" href="/tags/C.html" title=c>cin >> sclass="tags" href="/tags/C.html" title=c>code> 读取一个单词࿰class="tags" href="/tags/C.html" title=c>c;直到没有更多输入。

3. 反转每个单词：

   • <class="tags" href="/tags/C.html" title=c>code>for(int i = s.size() - 1; i >= 0; i--)class="tags" href="/tags/C.html" title=c>code>：我们使用一个从单词末尾到开头的 <class="tags" href="/tags/C.html" title=c>code>forclass="tags" href="/tags/C.html" title=c>code> 循环࿰class="tags" href="/tags/C.html" title=c>c;通过访问每个字符并逆序输出࿰class="tags" href="/tags/C.html" title=c>c;来实现反转操作。

4. 输出每个单词：

   • <class="tags" href="/tags/C.html" title=c>code>class="tags" href="/tags/C.html" title=c>cout << s[i];class="tags" href="/tags/C.html" title=c>code>：逐个输出反转后的字符。

5. 换行：

   • 每个单词输出后࿰class="tags" href="/tags/C.html" title=c>c;使用 <class="tags" href="/tags/C.html" title=c>code>class="tags" href="/tags/C.html" title=c>cout << endl;class="tags" href="/tags/C.html" title=c>code> 换行࿰class="tags" href="/tags/C.html" title=c>c;确保每个单词占一行。

思路分析

这段代码通过遍历每个字符并从末尾到开头进行输出来实现反转。通过这种手动操作字符的方式࿰class="tags" href="/tags/C.html" title=c>c;能够准确地完成任务。它的优点是直接且易于理解࿰class="tags" href="/tags/C.html" title=c>c;但缺点是代码稍显冗长࿰class="tags" href="/tags/C.html" title=c>c;且没有利用C++标准库提供的便捷工具。

---

💯二、老师的第一种做法

老师给出的第一种做法是通过手动交换字符串中的字符来反转单词。下面是老师的代码实现：

代码实现：

<class="tags" href="/tags/C.html" title=c>code class="tags" href="/tags/C.html" title=c>class="prism language-class="tags" href="/tags/C.html" title=c>cpp">class="tags" href="/tags/C.html" title=c>class="token maclass="tags" href="/tags/C.html" title=c>cro property">class="tags" href="/tags/C.html" title=c>class="token direclass="tags" href="/tags/C.html" title=c>ctive-hash">#class="tags" href="/tags/C.html" title=c>class="token direclass="tags" href="/tags/C.html" title=c>ctive keyword">inclass="tags" href="/tags/C.html" title=c>clude class="tags" href="/tags/C.html" title=c>class="token string"><iostream>
class="tags" href="/tags/C.html" title=c>class="token maclass="tags" href="/tags/C.html" title=c>cro property">class="tags" href="/tags/C.html" title=c>class="token direclass="tags" href="/tags/C.html" title=c>ctive-hash">#class="tags" href="/tags/C.html" title=c>class="token direclass="tags" href="/tags/C.html" title=c>ctive keyword">inclass="tags" href="/tags/C.html" title=c>clude class="tags" href="/tags/C.html" title=c>class="token string"><class="tags" href="/tags/C.html" title=c>cstring>
class="tags" href="/tags/C.html" title=c>class="token keyword">using class="tags" href="/tags/C.html" title=c>class="token keyword">namespaclass="tags" href="/tags/C.html" title=c>ce stdclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;

class="tags" href="/tags/C.html" title=c>class="token keyword">int class="tags" href="/tags/C.html" title=c>class="token funclass="tags" href="/tags/C.html" title=c>ction">mainclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)
class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">{
    string strclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
    class="tags" href="/tags/C.html" title=c>class="token keyword">whileclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(class="tags" href="/tags/C.html" title=c>cin class="tags" href="/tags/C.html" title=c>class="token operator">>> strclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)
    class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">{
        class="tags" href="/tags/C.html" title=c>class="token keyword">int left class="tags" href="/tags/C.html" title=c>class="token operator">= class="tags" href="/tags/C.html" title=c>class="token number">0class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
        class="tags" href="/tags/C.html" title=c>class="token keyword">int right class="tags" href="/tags/C.html" title=c>class="token operator">= strclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">.class="tags" href="/tags/C.html" title=c>class="token funclass="tags" href="/tags/C.html" title=c>ction">sizeclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">) class="tags" href="/tags/C.html" title=c>class="token operator">- class="tags" href="/tags/C.html" title=c>class="token number">1class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
        class="tags" href="/tags/C.html" title=c>class="token keyword">whileclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(left class="tags" href="/tags/C.html" title=c>class="token operator">< rightclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)
        class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">{
            class="tags" href="/tags/C.html" title=c>class="token keyword">class="tags" href="/tags/C.html" title=c>char tmp class="tags" href="/tags/C.html" title=c>class="token operator">= strclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">[leftclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">]class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
            strclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">[leftclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">] class="tags" href="/tags/C.html" title=c>class="token operator">= strclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">[rightclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">]class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
            strclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">[rightclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">] class="tags" href="/tags/C.html" title=c>class="token operator">= tmpclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
            leftclass="tags" href="/tags/C.html" title=c>class="token operator">++class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
            rightclass="tags" href="/tags/C.html" title=c>class="token operator">--class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
        class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">}
        class="tags" href="/tags/C.html" title=c>cout class="tags" href="/tags/C.html" title=c>class="token operator"><< str class="tags" href="/tags/C.html" title=c>class="token operator"><< endlclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
    class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">}
    
    class="tags" href="/tags/C.html" title=c>class="token keyword">return class="tags" href="/tags/C.html" title=c>class="token number">0class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">}
class="tags" href="/tags/C.html" title=c>code>

代码解析

老师的做法同样采用了字符交换的方式来反转每个单词。其关键点在于通过两个指针从字符串的两端向中间移动࿰class="tags" href="/tags/C.html" title=c>c;交换字符࿰class="tags" href="/tags/C.html" title=c>c;直到完成反转。

1. 初始化两个指针：

   • <class="tags" href="/tags/C.html" title=c>code>int left = 0; int right = str.size() - 1;class="tags" href="/tags/C.html" title=c>code>：<class="tags" href="/tags/C.html" title=c>code>leftclass="tags" href="/tags/C.html" title=c>code> 和 <class="tags" href="/tags/C.html" title=c>code>rightclass="tags" href="/tags/C.html" title=c>code> 分别是指向字符串开始和结束的两个指针。

2. 交换字符：

   • <class="tags" href="/tags/C.html" title=c>code>class="tags" href="/tags/C.html" title=c>char tmp = str[left]; str[left] = str[right]; str[right] = tmp;class="tags" href="/tags/C.html" title=c>code>：通过一个临时变量 <class="tags" href="/tags/C.html" title=c>code>tmpclass="tags" href="/tags/C.html" title=c>code> 来交换 <class="tags" href="/tags/C.html" title=c>code>str[left]class="tags" href="/tags/C.html" title=c>code> 和 <class="tags" href="/tags/C.html" title=c>code>str[right]class="tags" href="/tags/C.html" title=c>code>。

3. 逐步移动指针：

   • <class="tags" href="/tags/C.html" title=c>code>left++class="tags" href="/tags/C.html" title=c>code> 和 <class="tags" href="/tags/C.html" title=c>code>right--class="tags" href="/tags/C.html" title=c>code>：交换后࿰class="tags" href="/tags/C.html" title=c>c;<class="tags" href="/tags/C.html" title=c>code>leftclass="tags" href="/tags/C.html" title=c>code> 指针向右移动࿰class="tags" href="/tags/C.html" title=c>c;<class="tags" href="/tags/C.html" title=c>code>rightclass="tags" href="/tags/C.html" title=c>code> 指针向左移动࿰class="tags" href="/tags/C.html" title=c>c;逐步将字符串反转。

4. 输出反转后的字符串：

   • <class="tags" href="/tags/C.html" title=c>code>class="tags" href="/tags/C.html" title=c>cout << str << endl;class="tags" href="/tags/C.html" title=c>code>：输出反转后的单词。

思路分析

老师的做法通过交换字符来反转字符串࿰class="tags" href="/tags/C.html" title=c>c;使用了双指针的技巧࿰class="tags" href="/tags/C.html" title=c>c;这种方法比我的做法更具效率࿰class="tags" href="/tags/C.html" title=c>c;因为它只需要一次遍历࿰class="tags" href="/tags/C.html" title=c>c;每次只交换两个字符。相比手动逐个输出字符࿰class="tags" href="/tags/C.html" title=c>c;这种方法更符合常见的反转思路࿰class="tags" href="/tags/C.html" title=c>c;代码更简洁。

---

💯三、C++ <class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code> 函数介绍

在C++标准库中࿰class="tags" href="/tags/C.html" title=c>c;提供了一个名为 <class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code> 的函数࿰class="tags" href="/tags/C.html" title=c>c;它可以轻松地反转一个容器（例如字符串、数组等）的元素顺序。该函数位于 <class="tags" href="/tags/C.html" title=c>code><algorithm>class="tags" href="/tags/C.html" title=c>code> 头文件中࿰class="tags" href="/tags/C.html" title=c>c;使用时非常方便。

<class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code> 函数原型：

<class="tags" href="/tags/C.html" title=c>code class="tags" href="/tags/C.html" title=c>class="prism language-class="tags" href="/tags/C.html" title=c>cpp">class="tags" href="/tags/C.html" title=c>class="token keyword">void class="tags" href="/tags/C.html" title=c>class="token funclass="tags" href="/tags/C.html" title=c>ction">reverseclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(Bidireclass="tags" href="/tags/C.html" title=c>ctionalIterator firstclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">, Bidireclass="tags" href="/tags/C.html" title=c>ctionalIterator lastclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
class="tags" href="/tags/C.html" title=c>code>

• first：指向待反转区间的起始元素的迭代器。
• last：指向待反转区间的结束元素的迭代器。

该函数会反转区间 <class="tags" href="/tags/C.html" title=c>code>[first, last)class="tags" href="/tags/C.html" title=c>code> 中的元素。

示例：

<class="tags" href="/tags/C.html" title=c>code class="tags" href="/tags/C.html" title=c>class="prism language-class="tags" href="/tags/C.html" title=c>cpp">string s class="tags" href="/tags/C.html" title=c>class="token operator">= class="tags" href="/tags/C.html" title=c>class="token string">"abclass="tags" href="/tags/C.html" title=c>cd"class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
class="tags" href="/tags/C.html" title=c>class="token funclass="tags" href="/tags/C.html" title=c>ction">reverseclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(sclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">.class="tags" href="/tags/C.html" title=c>class="token funclass="tags" href="/tags/C.html" title=c>ction">beginclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">, sclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">.class="tags" href="/tags/C.html" title=c>class="token funclass="tags" href="/tags/C.html" title=c>ction">endclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
class="tags" href="/tags/C.html" title=c>cout class="tags" href="/tags/C.html" title=c>class="token operator"><< s class="tags" href="/tags/C.html" title=c>class="token operator"><< endlclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">; class="tags" href="/tags/C.html" title=c>class="token class="tags" href="/tags/C.html" title=c>comment">// 输出 "dclass="tags" href="/tags/C.html" title=c>cba"
class="tags" href="/tags/C.html" title=c>code>

优点

• 简洁：C++ <class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code> 函数将反转操作封装得非常简洁。只需调用一次 <class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code>࿰class="tags" href="/tags/C.html" title=c>c;就能完成字符串或数组的反转࿰class="tags" href="/tags/C.html" title=c>c;代码更加清晰易懂。
• 高效：<class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code> 内部实现通常采用类似于双指针交换的方式࿰class="tags" href="/tags/C.html" title=c>c;性能非常高。

---

💯四、老师的第二种做法：使用 <class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code> 函数

老师的第二种做法直接利用了 C++ STL 中的 <class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code> 函数࿰class="tags" href="/tags/C.html" title=c>c;这使得反转操作变得更加简便。

代码实现：

<class="tags" href="/tags/C.html" title=c>code class="tags" href="/tags/C.html" title=c>class="prism language-class="tags" href="/tags/C.html" title=c>cpp">class="tags" href="/tags/C.html" title=c>class="token maclass="tags" href="/tags/C.html" title=c>cro property">class="tags" href="/tags/C.html" title=c>class="token direclass="tags" href="/tags/C.html" title=c>ctive-hash">#class="tags" href="/tags/C.html" title=c>class="token direclass="tags" href="/tags/C.html" title=c>ctive keyword">inclass="tags" href="/tags/C.html" title=c>clude class="tags" href="/tags/C.html" title=c>class="token string"><iostream>
class="tags" href="/tags/C.html" title=c>class="token maclass="tags" href="/tags/C.html" title=c>cro property">class="tags" href="/tags/C.html" title=c>class="token direclass="tags" href="/tags/C.html" title=c>ctive-hash">#class="tags" href="/tags/C.html" title=c>class="token direclass="tags" href="/tags/C.html" title=c>ctive keyword">inclass="tags" href="/tags/C.html" title=c>clude class="tags" href="/tags/C.html" title=c>class="token string"><string>
class="tags" href="/tags/C.html" title=c>class="token maclass="tags" href="/tags/C.html" title=c>cro property">class="tags" href="/tags/C.html" title=c>class="token direclass="tags" href="/tags/C.html" title=c>ctive-hash">#class="tags" href="/tags/C.html" title=c>class="token direclass="tags" href="/tags/C.html" title=c>ctive keyword">inclass="tags" href="/tags/C.html" title=c>clude class="tags" href="/tags/C.html" title=c>class="token string"><algorithm>
class="tags" href="/tags/C.html" title=c>class="token keyword">using class="tags" href="/tags/C.html" title=c>class="token keyword">namespaclass="tags" href="/tags/C.html" title=c>ce stdclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;

class="tags" href="/tags/C.html" title=c>class="token keyword">int class="tags" href="/tags/C.html" title=c>class="token funclass="tags" href="/tags/C.html" title=c>ction">mainclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)
class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">{
    string strclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
    class="tags" href="/tags/C.html" title=c>class="token keyword">while class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(class="tags" href="/tags/C.html" title=c>cin class="tags" href="/tags/C.html" title=c>class="token operator">>> strclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)
    class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">{
        class="tags" href="/tags/C.html" title=c>class="token funclass="tags" href="/tags/C.html" title=c>ction">reverseclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(strclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">.class="tags" href="/tags/C.html" title=c>class="token funclass="tags" href="/tags/C.html" title=c>ction">beginclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">, strclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">.class="tags" href="/tags/C.html" title=c>class="token funclass="tags" href="/tags/C.html" title=c>ction">endclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
        class="tags" href="/tags/C.html" title=c>cout class="tags" href="/tags/C.html" title=c>class="token operator"><< str class="tags" href="/tags/C.html" title=c>class="token operator"><< endlclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
    class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">}
    class="tags" href="/tags/C.html" title=c>class="token keyword">return class="tags" href="/tags/C.html" title=c>class="token number">0class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">}
class="tags" href="/tags/C.html" title=c>code>

代码解析

这段代码通过 <class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code> 函数反转字符串：

1. 使用 <class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code> 函数：

   • <class="tags" href="/tags/C.html" title=c>code>reverse(str.begin(), str.end());class="tags" href="/tags/C.html" title=c>code>：直接使用 <class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code> 函数来反转字符串 <class="tags" href="/tags/C.html" title=c>code>strclass="tags" href="/tags/C.html" title=c>code>。

2. 输出反转后的字符串：

   • <class="tags" href="/tags/C.html" title=c>code>class="tags" href="/tags/C.html" title=c>cout << str << endl;class="tags" href="/tags/C.html" title=c>code>：输出每个反转后的单词࿰class="tags" href="/tags/C.html" title=c>c;并换行。

思路分析

这种做法通过使用 C++ STL 中的现成函数来简化代码。<class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code> 函数提供了高效且简洁的反转操作࿰class="tags" href="/tags/C.html" title=c>c;比手动交换字符或逐个输出字符的方法要简单得多。

---

💯五、对比分析

1. 我的做法：

   • 优点：代码简单࿰class="tags" href="/tags/C.html" title=c>c;容易理解࿰class="tags" href="/tags/C.html" title=c>c;适用于初学者。
   • 缺点：冗长࿰class="tags" href="/tags/C.html" title=c>c;效率较低࿰class="tags" href="/tags/C.html" title=c>c;特别是手动反转每个字符时࿰class="tags" href="/tags/C.html" title=c>c;不够高效。

2. 老师的第一种做法：

   • 优点：通过双指针交换字符࿰class="tags" href="/tags/C.html" title=c>c;比手动输出字符更高效。
   • 缺点：代码较为复杂࿰class="tags" href="/tags/C.html" title=c>c;理解起来可能稍微困难。

3. 老师的第二种做法：

   • 优点：使用 <class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code> 函数࿰class="tags" href="/tags/C.html" title=c>c;代码最简洁࿰class="tags" href="/tags/C.html" title=c>c;符合C++的标准库优势࿰class="tags" href="/tags/C.html" title=c>c;效率高。
   • 缺点：可能需要对 <class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code> 函数有一定的了解。

---

💯六、拓展

除了 <class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code> 函数外࿰class="tags" href="/tags/C.html" title=c>c;我们还可以用其他方式来处理字符串或数组的反转操作：

1. 利用栈：将字符压入栈中࿰class="tags" href="/tags/C.html" title=c>c;然后从栈中弹出字符来实现反转。
2. 递归：通过递归函数逐步将字符串或数组的字符进行反转。

---

💯小结

通过对比不同的做法࿰class="tags" href="/tags/C.html" title=c>c;我们可以看到࿰class="tags" href="/tags/C.html" title=c>c;C++提供了多种有效的反转策略。通过手动字符交换、使用 <class="tags" href="/tags/C.html" title=c>code>reverseclass="tags" href="/tags/C.html" title=c>code> 函数࿰class="tags" href="/tags/C.html" title=c>c;甚至使用 STL 容器的其他方法࿰class="tags" href="/tags/C.html" title=c>c;我们可以灵活地选择最适合问题需求的解决方案。在实际开发中࿰class="tags" href="/tags/C.html" title=c>c;选择合适的工具和方法࿰class="tags" href="/tags/C.html" title=c>c;不仅能提高代码的可读性࿰class="tags" href="/tags/C.html" title=c>c;还能提高程序的效率。

---

class="tags" href="/tags/C.html" title=c>c="https://img-blog.class="tags" href="/tags/C.html" title=c>csdnimg.class="tags" href="/tags/C.html" title=c>cn/direclass="tags" href="/tags/C.html" title=c>ct/00d4fdeb7b0d4dbb99e88f325ef249d8.gif#piclass="tags" href="/tags/C.html" title=c>c_class="tags" href="/tags/C.html" title=c>center" alt="在这里插入图片描述" width="1000" height="100" />

---

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最开始的解法不通过

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class="tags" href="/tags/C.html" title=c>code>

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老师优化后通过

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            class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">}
            class="tags" href="/tags/C.html" title=c>cout class="tags" href="/tags/C.html" title=c>class="token operator"><< endlclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
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        class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">}
        class="tags" href="/tags/C.html" title=c>class="token keyword">else class="tags" href="/tags/C.html" title=c>class="token keyword">if class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(i class="tags" href="/tags/C.html" title=c>class="token operator">== sclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">.class="tags" href="/tags/C.html" title=c>class="token funclass="tags" href="/tags/C.html" title=c>ction">sizeclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">) class="tags" href="/tags/C.html" title=c>class="token operator">- class="tags" href="/tags/C.html" title=c>class="token number">2class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)
        class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">{
            class="tags" href="/tags/C.html" title=c>class="token keyword">for class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">(class="tags" href="/tags/C.html" title=c>class="token keyword">int j class="tags" href="/tags/C.html" title=c>class="token operator">= iclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">; j class="tags" href="/tags/C.html" title=c>class="token operator">>= indexclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">; jclass="tags" href="/tags/C.html" title=c>class="token operator">--class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">)
            class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">{
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            class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">}
            class="tags" href="/tags/C.html" title=c>cout class="tags" href="/tags/C.html" title=c>class="token operator"><< endlclass="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
        class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">}
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    class="tags" href="/tags/C.html" title=c>class="token keyword">return class="tags" href="/tags/C.html" title=c>class="token number">0class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">;
class="tags" href="/tags/C.html" title=c>class="token punclass="tags" href="/tags/C.html" title=c>ctuation">}
class="tags" href="/tags/C.html" title=c>code>