LeetCode(一）Reverse Words in a String III

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#LeetCode #字符串逆序 #算法 #Reverse Words in a String III

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本文介绍了一种算法，用于反转字符串中每个单词的字符顺序，同时保持原有的空格和单词顺序不变。通过将字符串分割为单词数组并逆序每个单词实现。

题目描述：
Given a string, you need to reverse the order of characters in each word within a sentence while still preserving whitespace and initial word order.

Example 1:
Input: “Let’s take LeetCode contest”
Output: “s’teL ekat edoCteeL tsetnoc”
Note: In the string, each word is separated by single space and there will not be any extra space in the string.

思路：
1、先将字符串分割成单词字符串数组
2、将每个单词逆序即可

class Solution {
	public String reverseWords(String s) {
       String[] strs = s.split("\\s");
       String reverseStr = "";
       for(int i = 0; i < strs.length; i++) {
    	   reverseStr += reverseEachWord(strs[i])+" ";
       }
       return reverseStr.trim();
    }
	
	public String reverseEachWord(String str) {
		char[] chs = str.toCharArray();
		for(int i = 0; i < chs.length/2; i++) {
			swap(chs, i, chs.length-1-i);
		}
		return String.valueOf(chs);
	}

	public void swap(char[] chs, int i, int j) {
		char tmp = chs[i];
		chs[i] = chs[j];
		chs[j] = tmp;
	}
}