[求助]1/1！+1/2！-1/3！……+1/8！怎么编？ - C语言论坛

新坏男人

等　级：新手上路
威　望：1
帖　子：38
专家分：0
注　册：2005-12-7

第 2 楼

得分:0

#include <stdio.h>

void main()
{
double pi=0;

double a=1.0,k=1.0;

for(int i=0;i<=10;i++)

{
pi+=k*1.0/a;
k=-k;
a++;
a*=a;
}

printf("%lf\n",pi);
}

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2005-12-20 22:02

jupiter_201

等　级：新手上路
帖　子：3
专家分：0
注　册：2005-12-21

第 4 楼

得分:0

main()
{
float sum=1,n,k=1,i,j;
for(j=2;j<=8;j++)
{n=1;

for(i=1;i<=j;i++)

n*=i;

sum=sum+1.0/n*k;

k=-k;

}

printf("\n%f",sum);

}
结果是:1.367882

2005-12-21 20:36