以长整数保存阶乘

Question

I am using the following code to get the Factorial, but it seems to be limited for me.

private Int64 GetFactorial(Int64 value)
{
    if (value <= 1)
    {
        return 1;
    }
    return value * GetFactorial(value - 1);
}

But it seems to only allow the values upto 65 on 66 th value, it provides a 0 as a result and the result is negative too if the value is 65 or near. What can I do to allow more values to work with, and get result with having the System.StackOverflowException ?

Answer 1

您可能要检查BigInteger结构，因为它允许任意大小的整数： http : //msdn.microsoft.com/zh-cn/library/system.numerics.biginteger(v=vs.110）。 aspx

Answer 2

Uint64可以为您带来更多收益，但不确定多少。