#!/usr/bin/env python
_sum = 1
for line in range(1, 1000):
    _sum = _sum * line
print _sum

#!/usr/bin/env python
_sum = 1
for line in range(1, 1001):
    _sum = _sum * line
print _sum

#include <conio.h>
#include <stdio.h>
#include <stdlib.h>
#include <windows.h>

#define NMAX 4000000

unsigned int result[NMAX];
unsigned int n;

void ReadFile()
{
	FILE * f = fopen("GIAITHUA.INP", "rt");
	if (f != NULL)
		fscanf(f, "%d", &n);
	fclose(f);
}

void WriteFile()
{
	FILE * f = fopen("GIAITHUA.OUT", "wt");
	
	if (f != NULL) 
	{
        int count = 1;
		for (unsigned int i = result[0]; i >= 1; --i)
		{
			if (count % 80 == 0) 
               fprintf(f, "\n");
			fprintf(f, "%d", result[i]);
			count++;
        }
	}
	fclose(f);
}

void Solve(unsigned int result[], unsigned int n) {
     
	unsigned int remainder;
	result[0] = 1;
	result[1] = 1;
	for (unsigned int i = 2; i <= n; ++i) 
	{
		remainder = 0;
		for (unsigned int j = 1; j <= result[0]; ++j) 
		{
			result[j] = result[j] * i + remainder;
			remainder = result[j] / 10;
			result[j] = result[j] % 10;
		}
		
		while (remainder > 0)
		{
			++result[0];
			result[result[0]] = remainder % 10;
			remainder /= 10;
		}
	}
}


int main() {
	wchar_t buff[100];
	ReadFile();
	DWORD dwStart = GetTickCount();
	Solve(result, n);
	WriteFile();
	DWORD dwInterval = GetTickCount() - dwStart;
	printf("The program pass %d times to complete", dwInterval);
	return 0;
}