Leetcode) 1816. Truncate Sentence c++

class Solution {
public:
    string truncateSentence(string s, int k) {
        string ans = "";
        for(int i =0; i<s.size();i++){
            if(s[i] == ' ' && --k==0) break; 
            ans += s[i];
        }
        return ans;
    }
};