[leetcode] 557. Reverse Words in a String III

题目：

---

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.

代码：

class Solution {
public:
    string reverseWord(string s){
        if(s.size() == 0) return s;
        for(int i = 0; i <= (s.size()-1)/2; i++){
            char temp = s[i];
            s[i] = s[s.size()-1-i];
            s[s.size()-1-i] = temp;
        }
        return s;
    }
    string reverseWords(string s) {
        vector<string> l;
        string res;
        int index = 0;
        while((index = s.find(" ")) != string::npos){
            string t = s.substr(0, index);
            s = s.substr(index+1);
            l.push_back(t);
        }
        l.push_back(s);
        for(int i = 0; i < l.size(); i++){
            string r = reverseWord(l[i]);
            if(i == 0) res = r;
            else res =res + ' ' + r;
        }
        return res;
    }
};