题解 | #字符串变形#

class Solution {
  public:
    string trans(string s, int n) {
        string tmp = "", res = "";
        for (int i = 0; i < n; i++) {
            if (s[i] == ' ') {
                res = tmp + " " + res; //倒序
                tmp = "";
            } else {
                tmp += s[i] > 90 ? s[i] - 32 : s[i] + 32; //反转大小写
            }
        }
        res = tmp + " " + res;
        res.erase(res.end() - 1);
        return res;
    }
};