以下程序运行时，从键盘上输入数字3，程序运行结果为_________。#include int main(void){int i,n;double sum=0.0,fz=2.0,fm=1.0,item,temp;printf("Enter n: ");scanf("%d",&n);for(i=1;i<=n;i++){item=fz/fm;sum=sum+item;temp=fz;fz=fz+fm;fm=temp;}printf("%.0lf\n",sum);return 0;}