class Solution {
    public int reverse(int x) {
        String str = String.valueOf(x);
        String res = "";
        boolean isMinus = false;
        if(str.charAt(0) == '-') {
            isMinus = true;
            str = str.substring(1);
        }
        int len = str.length();
        for(int i = len-1;i>-1;i--) {
            res += str.charAt(i);
        }
        if(isMinus) {
            res = '-' + res;
        }
        
        double a = Double.parseDouble(res);       
        if((a > (Math.pow(2,31) - 1)) || (a < (-Math.pow(2,31)))) {
            a = 0;
        }
        return (int)a;      
    }
}