習題2-4 子序列的和(subsequence) 演算法競賽入門經典 第二版
#include<iostream>
#include<cstdio>
#include<cmath>
using namespace std;
int main(){
double n,m;
double sum=0;
while(scanf("%lf %lf",&n,&m)==2&&(n!=0||m!=0)){
while(n<=m){
sum+=1/(n*n);
n++;
}
printf("%.5lf\n",sum);
sum=0;
}
return 0;
}
當變數n,m為int型別時,內層while迴圈 改為 sum+=1/n/n;