题解 | #字符串变形#

class Solution {
public:
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param s string字符串 
     * @param n int整型 
     * @return string字符串
     */
    string trans(string s, int n) 
    {
        // write code here
        vector<string> words;
        int startPos = 0;
        for (int i = 0; i <= s.size(); i++)
        {
            if (s[i] == ' ' || i == s.size())
            {
                int length = i - startPos;
                string word = s.substr(startPos, length);
                words.push_back(word);
                startPos = i + 1;
            }
        }
        string ans;
        for (auto it = words.rbegin();it != words.rend();it++)
        {
            for (int i = 0;i < (*it).size();i++)
            {
                if((*it)[i] >= 'a' && (*it)[i] <= 'z')
                {
                    ans += (*it)[i] - 32;
                    //continue;
                }
                else if ((*it)[i] >= 'A' && (*it)[i] <= 'Z')
                {
                    ans += (*it)[i] + 32;
                    //continue;
                }
            }
            if (it != words.rend())
            {
                ans += ' ';
            }
        }
        return ans.substr(0, ans.length() - 1);  //最后一个单词后面多加了一个空格，所以剪掉
    }
};