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feat: add solutions to lc problem: No.0917
No.0917.Reverse Only Letters
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‎solution/0900-0999/0917.Reverse Only Letters/README.md

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<!-- 这里写题目描述 -->
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<p>给定一个字符串&nbsp;<code>S</code>，返回&nbsp;&ldquo;反转后的&rdquo;&nbsp;字符串，其中不是字母的字符都保留在原地，而所有字母的位置发生反转。</p>
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<p>给你一个字符串 <code>s</code> ，根据下述规则反转字符串：</p>
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<ul>
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<li>所有非英文字母保留在原有位置。</li>
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<li>所有英文字母（小写或大写）位置反转。</li>
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</ul>
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<p>返回反转后的 <code>s</code><em> 。</em></p>
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<p>&nbsp;</p>
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<p><strong>示例 1：</strong></p>
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<pre><strong>输入：</strong>&quot;ab-cd&quot;
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<strong>输出：</strong>&quot;dc-ba&quot;
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<pre>
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<strong>输入：</strong>s = "ab-cd"
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<strong>输出：</strong>"dc-ba"
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</pre>
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<ol>
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</ol>
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<p><strong>示例 2：</strong></p>
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<pre><strong>输入：</strong>&quot;a-bC-dEf-ghIj&quot;
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<strong>输出：</strong>&quot;j-Ih-gfE-dCba&quot;
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<pre>
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<strong>输入：</strong>s = "a-bC-dEf-ghIj"
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<strong>输出：</strong>"j-Ih-gfE-dCba"
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</pre>
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<ol>
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</ol>
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<p><strong>示例 3：</strong></p>
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<pre><strong>输入：</strong>&quot;Test1ng-Leet=code-Q!&quot;
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<strong>输出：</strong>&quot;Qedo1ct-eeLg=ntse-T!&quot;
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<pre>
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<strong>输入：</strong>s = "Test1ng-Leet=code-Q!"
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<strong>输出：</strong>"Qedo1ct-eeLg=ntse-T!"
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</pre>
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<p>&nbsp;</p>
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<p><strong>提示：</strong></p>
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<p><strong>提示</strong></p>
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<ol>
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<li><code>S.length &lt;= 100</code></li>
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<li><code>33 &lt;= S[i].ASCIIcode &lt;= 122</code>&nbsp;</li>
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<li><code>S</code> 中不包含&nbsp;<code>\</code> or <code>&quot;</code></li>
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</ol>
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<ul>
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<li><code>1 &lt;= s.length &lt;= 100</code></li>
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<li><code>s</code> 仅由 ASCII 值在范围 <code>[33, 122]</code> 的字符组成</li>
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<li><code>s</code> 不含 <code>'\"'</code> 或 <code>'\\'</code></li>
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</ul>
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## 解法
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<!-- 这里可写通用的实现逻辑 -->
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双指针遍历字符串，交换两个指针指向的字母。
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<!-- tabs:start -->
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### **Python3**
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```python
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class Solution:
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def reverseOnlyLetters(self, s: str) -> str:
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s = list(s)
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i, j = 0, len(s) - 1
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while i < j:
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while i < j and not s[i].isalpha():
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i += 1
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while i < j and not s[j].isalpha():
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j -= 1
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if i < j:
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s[i], s[j] = s[j], s[i]
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i, j = i + 1, j - 1
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return ''.join(s)
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```
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### **Java**
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```java
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class Solution {
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public String reverseOnlyLetters(String s) {
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char[] chars = s.toCharArray();
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int i = 0, j = s.length() - 1;
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while (i < j) {
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while (i < j && !Character.isLetter(chars[i])) {
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++i;
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}
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while (i < j && !Character.isLetter(chars[j])) {
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--j;
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}
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if (i < j) {
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char t = chars[i];
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chars[i] = chars[j];
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chars[j] = t;
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++i;
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--j;
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}
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}
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return new String(chars);
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}
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}
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```
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### **C++**
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```cpp
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class Solution {
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public:
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string reverseOnlyLetters(string s) {
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int i = 0, j = s.size() - 1;
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while (i < j)
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{
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while (i < j && !isalpha(s[i])) ++i;
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while (i < j && !isalpha(s[j])) --j;
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if (i < j)
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{
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swap(s[i], s[j]);
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++i;
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--j;
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}
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}
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return s;
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}
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};
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```
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### **Go**
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```go
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func reverseOnlyLetters(s string) string {
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ans := []rune(s)
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i, j := 0, len(s)-1
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for i < j {
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for i < j && !unicode.IsLetter(ans[i]) {
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i++
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}
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for i < j && !unicode.IsLetter(ans[j]) {
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j--
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}
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if i < j {
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ans[i], ans[j] = ans[j], ans[i]
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i++
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j--
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}
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}
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return string(ans)
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}
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```
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### **...**

‎solution/0900-0999/0917.Reverse Only Letters/README_EN.md

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## Description
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<p>Given a string <code>S</code>, return the &quot;reversed&quot; string where all characters that are not a letter&nbsp;stay in the same place, and all letters reverse their positions.</p>
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<p>Given a string <code>s</code>, reverse the string according to the following rules:</p>
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<p>&nbsp;</p>
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<div>
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<div>
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<div>
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<ol>
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<ul>
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<li>All the characters that are not English letters remain in the same position.</li>
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<li>All the English letters (lowercase or uppercase) should be reversed.</li>
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</ul>
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</ol>
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</div>
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</div>
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</div>
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<div>
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<p>Return <code>s</code><em> after reversing it</em>.</p>
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<p>&nbsp;</p>
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<p><strong>Example 1:</strong></p>
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<pre>
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<strong>Input: </strong><span id="example-input-1-1">&quot;ab-cd&quot;</span>
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<strong>Output: </strong><span id="example-output-1">&quot;dc-ba&quot;</span>
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<pre><strong>Input:</strong> s = "ab-cd"
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<strong>Output:</strong> "dc-ba"
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</pre><p><strong>Example 2:</strong></p>
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<pre><strong>Input:</strong> s = "a-bC-dEf-ghIj"
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<strong>Output:</strong> "j-Ih-gfE-dCba"
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</pre><p><strong>Example 3:</strong></p>
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<pre><strong>Input:</strong> s = "Test1ng-Leet=code-Q!"
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<strong>Output:</strong> "Qedo1ct-eeLg=ntse-T!"
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</pre>
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<div>
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<p><strong>Example 2:</strong></p>
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<pre>
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<strong>Input: </strong><span id="example-input-2-1">&quot;a-bC-dEf-ghIj&quot;</span>
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<strong>Output: </strong><span id="example-output-2">&quot;j-Ih-gfE-dCba&quot;</span>
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</pre>
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<div>
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<p><strong>Example 3:</strong></p>
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<pre>
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<strong>Input: </strong><span id="example-input-3-1">&quot;Test1ng-Leet=code-Q!&quot;</span>
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<strong>Output: </strong><span id="example-output-3">&quot;Qedo1ct-eeLg=ntse-T!&quot;</span>
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</pre>
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<p>&nbsp;</p>
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<p><strong>Constraints:</strong></p>
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<div>
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<p><strong><span>Note:</span></strong></p>
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<ol>
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<li><code>S.length &lt;= 100</code></li>
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<li><code>33 &lt;= S[i].ASCIIcode &lt;= 122</code>&nbsp;</li>
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<li><code>S</code> doesn&#39;t contain <code>\</code> or <code>&quot;</code></li>
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</ol>
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</div>
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</div>
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</div>
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</div>
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<ul>
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<li><code>1 &lt;= s.length &lt;= 100</code></li>
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<li><code>s</code> consists of characters with ASCII values in the range <code>[33, 122]</code>.</li>
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<li><code>s</code> does not contain <code>&#39;\&quot;&#39;</code> or <code>&#39;\\&#39;</code>.</li>
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</ul>
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## Solutions
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### **Python3**
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```python
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class Solution:
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def reverseOnlyLetters(self, s: str) -> str:
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s = list(s)
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i, j = 0, len(s) - 1
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while i < j:
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while i < j and not s[i].isalpha():
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i += 1
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while i < j and not s[j].isalpha():
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j -= 1
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if i < j:
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s[i], s[j] = s[j], s[i]
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i, j = i + 1, j - 1
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return ''.join(s)
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```
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### **Java**
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```java
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class Solution {
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public String reverseOnlyLetters(String s) {
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char[] chars = s.toCharArray();
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int i = 0, j = s.length() - 1;
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while (i < j) {
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while (i < j && !Character.isLetter(chars[i])) {
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++i;
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}
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while (i < j && !Character.isLetter(chars[j])) {
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--j;
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}
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if (i < j) {
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char t = chars[i];
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chars[i] = chars[j];
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chars[j] = t;
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++i;
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--j;
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}
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}
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return new String(chars);
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}
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}
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```
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### **C++**
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```cpp
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class Solution {
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public:
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string reverseOnlyLetters(string s) {
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int i = 0, j = s.size() - 1;
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while (i < j)
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{
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while (i < j && !isalpha(s[i])) ++i;
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while (i < j && !isalpha(s[j])) --j;
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if (i < j)
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{
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swap(s[i], s[j]);
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++i;
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--j;
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}
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}
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return s;
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}
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};
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```
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### **Go**
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```go
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func reverseOnlyLetters(s string) string {
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ans := []rune(s)
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i, j := 0, len(s)-1
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for i < j {
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for i < j && !unicode.IsLetter(ans[i]) {
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i++
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}
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for i < j && !unicode.IsLetter(ans[j]) {
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j--
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}
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if i < j {
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ans[i], ans[j] = ans[j], ans[i]
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i++
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j--
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}
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}
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return string(ans)
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}
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```
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### **...**

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