C语言 计算1+1/2!+1/3!+1/4! +…+1/n!的值

Posted 2021-05-20 Aiden (winner)

#include<stdio.h>
int fun(int n){
	int i = 0;
	int flag = 1; //存返回值
	if (0 == n || 1 == n){
		return 1;
	}else{
		for (i = 2; i <= n; i++){
			flag *= i;
		}
		return flag;
	}
}
double sum(int n){//求和函数
	int i;                      
	double sum = 0;
	for (i = 1; i <= n; i++){
		sum += 1.0 / fun(i);
	}
	return sum;
}
void main(){
	int n;                 
	printf("请输入项数");
	scanf("%d",&n);
	printf("sum = %lf", sum(n));
}