Leetcode reverse integer

#include<bits/stdc++.h>
using namespace std;
class Solution {
public:
    int reverse(int x) {
        string s = to_string (x);
        if ( s[0] =='-') s.erase(s.begin());
        std::reverse(s.begin(),s.end());
        for (int i=0;i<s.size();i++){
            if ( s[i]!='0'){
                s=s.substr(i);
                break;
            }
        }

        long long real = stoll ( s);
        if ( real > 2147483648 ) return 0; // 2^31-1 = 2147483648
        return x>0? stoi(s) : -stoi(s);
    }
};