C语言 计算1-1/3+1/5-1/7+…+1/(2*n+1)的值

Posted 2021-05-20 Aiden (winner)

#include<stdio.h>
void fun(float *sn,int n){
	float s=0,flag=-1.0;
	int i;
	for(i=0;i<n;i++){
		flag=-1*flag;
		s+=flag/(2*i+1);
	}
	*sn=s;
	printf("前%d项结果为：%f",n,*sn);
}
void main(){
	float sn;
	int n;
	printf("请输入项数：");
	scanf("%d",&n);
	fun(&sn,n);
}