利用while,for,do-while循环语句计算求和问题：S=1-1/2+1/3-1/4+……1/999-1/1000

Answer 1

在excel 中用vba 输入以下代码即可：（vb中也可以）
Sub aaa()
Dim s, i, k, m
For i = 1 To 1000
If i Mod 2 = 0 Then
k = 0 - i
Else
k = i
End If
s = s + 1 / k
Next
MsgBox Format(s, "0.00")
End Sub

Answer 2

#include<stdio.h>
int main()
{
float i,a=1,sum=0;
for(i=1;i<=1000;i++)
{sum+=a/i;
a=-a;
}
printf("%f",sum);
return 0;
}

Answer 3

#include "stdio.h"
void main()
{
int s=1;
double n,t,p;
n=1.0;
t=1;
p=0;
while(n<=1000)
{
p+=t;
n+=1;
s=-s;
t=s/n;
}
printf("%f\n",p);
}