C++ 大数阶乘求取--数组实现代码

#include <iostream>
#include <cstdlib>
#include <string>
#include <stdio.h>

using namespace std;

int main(int argc, char *argv[])
{
int n = 0;
cout << "Please input the number for Factorial operate : ";
cin  >> n;

int LargeNumberFactorial[10000] = {0};
LargeNumberFactorial[0]    = 1;        // 0! = 1
LargeNumberFactorial[1]    = 1;        // 第一位对应的数值初始为 1
int          digit         = 1;        // n!阶乘求取的位数初始为 1

for (int i = 1; i <= n; i++)           // 1,2,3,...,n
{
for (int j = 1; j <= digit; j++)
{
LargeNumberFactorial[j] *= i;
}

for (int j = 1; j <= digit; j++)
{
if (LargeNumberFactorial[j] > 10)
{
for (int r = 1; r <= digit; r++)
{
if (LargeNumberFactorial[digit] > 9)
{
digit++;
}
LargeNumberFactorial[r+1] += LargeNumberFactorial[r]/10;
LargeNumberFactorial[r]   %= 10;
}
}
}
}

cout << n << "!= ";
for (int k = digit; k > 0; k--)
{
cout << LargeNumberFactorial[k];
}
cout << endl;

return 0;
}