hdu 4627 The Unsolvable Problem

http://acm.hdu.edu.cn/showproblem.php?pid=4627

分类讨论一下就可以

代码：

#include<iostream>

#include<cstdio>

#include<algorithm>

#include<string>

#include<cstring>

#include<cmath>

#include<set>

using namespace std;



typedef long long ll;

typedef pair<double,double>ppd;

const double PI = acos(-1.);

const double eps = (1e-9);

const int N=2005;

const int M=2000000;

const int K=27;



int main()

{

    //freopen("data.in","r",stdin);

    int T;

    scanf("%d",&T);

    while(T--)

    {

       ll n;

       cin>>n;

       if(n==2)

       {cout<<"1"<<endl;continue;}

       ll a=n/2;

       ll b=n-a;

       if(a!=b)

       {cout<<(a*b)<<endl;continue;}

       if((a&1)==0)

       {cout<<(a-1)*(a+1)<<endl;continue;}

       cout<<(a-2)*(a+2)<<endl;

    }

    return 0;

}