Reverse Integer
Reverse digits of an integer.
Example1: x = 123, return 321
Example2: x = -123, return -321
public class Solution { public int reverse(int x) { int ret = 0; int i = 10; int x_cpy = x; ArrayList<Integer> array = new ArrayList<Integer>(); while (x!=0) { int di = x%10; array.add(Math.abs(di)); x /= 10; } int temp= (int) Math.pow(10,(array.size()-1)); for(i=0;i<array.size();i++){ ret += array.get(i)*temp; temp /= 10; } if (x_cpy<0) { return 0-ret; } return ret; } }