Reverse digits of an integer.

Example1: x = 123, return 321
Example2: x = -123, return -321

Here are some good questions to ask before coding. Bonus points for you if you have already thought through this!

If the integer's last digit is 0, what should the output be? ie, cases such as 10, 100.

Did you notice that the reversed integer might overflow? Assume the input is a 32-bit integer, then the reverse of 1000000003 overflows. How should you handle such cases?

For the purpose of this problem, assume that your function returns 0 when the reversed integer overflows.

Update (2014-11-10):
Test cases had been added to test the overflow behavior.

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本題當時做的時候出現了主要問題就是溢位， 由於沒有考慮到當x == Integer.MIN_VALUE時，reverse過後依然會溢位的情況。參考了網上有關該題的程式碼，好多都沒有考慮溢位，在這兒總結一下。

public int reverse(int x)
	{
		int negative = 1;
		
		if(x <= Integer.MIN_VALUE)
			return 0;
		if(x < 0)
		{
			x = -x;
			negative = -1;
		}
		
		long y = x % 10;
		
		while(x / 10 != 0)
		{
			x /= 10;
			y *= 10;
			y += x %10;
		}
		
		if(y > Integer.MAX_VALUE)
			return 0;
		else
			return (int)y * negative;
	}