The to_string() series of functions convert numeric values to string form

class Solution {
    
    
public:
    vector<string> simplifiedFractions(int n) {
    
    
        vector<string> ans;
        for(int y=2;y<=n;y++){
    
    
            for(int x=1;x<y;x++){
    
    
                if(__gcd(x,y)==1){
    
    
                    ans.push_back(to_string(x)+'/'+to_string(y));
                }
            }
        }
        return ans;
    }
};