Codeforces 194B

题意:在n*n的上从左下角开始,每次走n+1个点画一个叉,问回到起点时一共画几个叉;

思路:gcd;

#include<cstdio>
#include<algorithm>
#include<cstring>
#include<iostream>
using namespace std;
long long n,m,num,t,a,b,r;
int i,j,k,rcount,shu,flag,yu,len;
long long gcd(long long a,long long b)
{
    long long c;
    c=a%b;
    while(c)
    {
        a=b;
        b=c;
        c=a%b;
    }
    return b;
}
int main()
{
   while(cin>>t)
   {
       while(t--)
       {
           cin>>n;
        a=4*n,b=n+1;
        num=4*n/gcd(a,b)+1;
        cout<<num<<endl;
       }
   }
   return 0;
}
时间: 2024-10-12 17:25:32

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