CF743C 题解

题目链接

\(Solution:\)

为什么这题有蓝啊\(QwQ\)。。。

\(\frac{1}{n}+\frac{1}{n+1}+\frac{1}{n(n+1)}=\frac{2}{n}\)

\(Code:\)

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
ll n;
inline ll read()
{
    ll sum=0,f=1;
    char ch=0;
    while(!isdigit(ch))
    {
        if(ch=='-') f=-1;
        ch=getchar();
    }
    while(isdigit(ch))
    {
        sum=(sum<<1)+(sum<<3)+(ch^48);
        ch=getchar(); 
    }
    return sum*f;
}
int main(void)
{
    n=read();
    if(n==1)
    {
        printf("-1\n");
        return 0;
    }
    printf("%lld %lld %lld\n",n,n+1,n*(n+1));
    return 0;
}