leetcode 7. Reverse Integer

class Solution {
public:
    int reverse(int x) {
        //cout<<x<<endl;
        long long ans = 0;
        int l = 1;
        if(x < 0){
            l = -1;
            x = -x;
        }
        while(x > 0){
            if(ans * 10 > 2147483647){ ans = 0;break;}
           ans = ans*10+x%10;
           x/=10;
        }
        return ans * l;
    }
};