Reverse Integer

package leetcode.xuyi;import org.junit.Test;/** * Created by ethan on 2015/5/9. */public class ReverseInteger {    public int reverse(int x) {        if(x==-2147483648 || x==2147483647)            return 0;        int positive_negitive = 1;        if (x<0){            x = -x;            positive_negitive = -1;        }        long  ans = 0;        while(x!=0){            int tmp = x%10;            x = x/10;            ans = ans*10+tmp;        }        if (ans>2147483647 ||(positive_negitive==-1 && ans-1>2147483647)){            return 0;        }        return  (int)ans*positive_negitive;    }    @Test    public void test6(){        int ans = reverse(601);        System.out.println(ans);    }}