Question

写程序计算并输出下列多项式值： Sn = 1 + 1/1! + 1/2! + 1/3! + 1/4! + ... + 1/n!

Answer 1

#include <stdio.h>
double fun(int n)
{
double t,sn=1.0;
int i,j;
for(i=1;i<=n;i++)
{
t=1.0;
for(j=1;j<=i;j++)
t*=j;
sn+=1.0/t;
}
return sn;
}
void main()
{
int n;
double s;
printf("\nInput n: ");
scanf("%d",&n);
s=fun(n);
printf("s=%f\n",s);
}

Answer 2

void main(){
float s=1;
int m=1,n;
cin>>n;
for (int i=1;i<n;i++){
m*=i;
s+=(float)1/m;
}
cout<<s;
}