蓝桥杯刷题--（3.11）

[Persistence]

//分数
#include<bits/stdc++.h>
using namespace std;
int gcd(int a,int b)
{
    return b?gcd(b,a%b):a;
}
int main() 
{
    int sum=0;
    int n=20;
    int k=1;
    while(n--)
    {
        sum+=k;
        k*=2;
    }
    cout<<sum<<'/'<<k/2;
}

https://www.lanqiao.cn/problems/610/learning/?page=4&first_category_id=1&sort=students_count&second_category_id=3