C语言_利用求阶乘函数Fact()，编程计算1!+2!+...+n!

利用求阶乘函数Fact()，编程计算1!+2!+…+n!

#include 
unsigned long Fact(unsigned int n);  //函数原型声明

int main () {
	int n,p;
	unsigned long sum = 0;
	printf("Input n:");
	scanf("%d",&n);
	for(int i = 1; i<= n; i++) {
		printf("%d!",i);
		if (i != n)
			printf(" + ");
		else 
			printf(" = ");
		sum += Fact(i); 
	}
	printf("%lu",sum);
	return 0;
}
//用迭代法计算n!
unsigned long Fact(unsigned int n) {
	unsigned int i;
	unsigned long result = 1;
	for(i=2; i<=n; i++)
		result *= i;
	return result;
}