#include<stdio.h>
int main()
{
float sum=0;
int i,n,a=2,b=1;
printf("请输入式子总数:");
scanf("%d",&n);
for(i=1;i<=n;i++)
{
printf("第%d个式子为:%d/%d\n",i,a,b);
sum+=(a/b);
a = a + b;
b = a-b;
}
printf("式子之和为:%f",sum);
return 0;
}