2200.cpp

杭电 acm部分代码 有兴趣的可以下载 谢谢

#include <stdio.h>
__int64 C[66][66];
int main() 
{
	__int64 i, j, sum;
	for (i = 1; i <= 60; i++)
	{
		C[i][0] = 1;
		C[i][1] = i;
	}
	for (i = 2; i <= 60; i++)
	{
		for (j = 1; j <= i; j++)
		{
			C[i][j] = C[i - 1][j - 1] +C[i - 1][j];
		}
	}
	while (scanf("%I64d", &i) == 1)
	{
		sum = 0;
		for (j = 2; j <= i; j++)
		{
			sum += C[i][j] * (j - 1);
		}
		printf("%I64d\n", sum);
	}
	return 0;
}