2109. Adding Spaces to a String

class Solution {
public:
    string addSpaces(string s, vector<int>& spaces) {
        int ind = 0;
        string ans = "";
        for (int i = 0; i < s.size(); i++) {
            if (ind < spaces.size() && i == spaces[ind]) { 
                ans += " ";
                ind++;
            }
            ans += s[i];
        }
        return ans;
    }
};