LeetCode.7： Reverse Integer

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my answer in CSharp codes:

public int Reverse(int x)
        {
            string value = x.ToString();
            string a = "";
            if (value.ElementAt(0).Equals('-'))
            {
                value = value.Remove(0,1);
                a = "-";
            }
            value = new string(value.ToCharArray().Reverse().ToArray());
            string ret = a + value;

            int iRet = 0;
            int.TryParse(ret,out iRet);

            return iRet;
        }

better answer from discuss:

public int reverse(int x)
{
    int result = 0;

    while (x != 0)
    {
        int tail = x % 10;
        int newResult = result * 10 + tail;
        if ((newResult - tail) / 10 != result)
        { return 0; }
        result = newResult;
        x = x / 10;
    }

    return result;
}