2020牛客暑期多校训练营（第七场）D.Fake News

D.Fake News

题目链接-D.Fake News


题目大意
判断$1^2+2^2+\dots +n^2$的和是否是一个平方数

解题思路

通过打表得出只有$n=1$或$n=24$的时候，$1^2+2^2+\dots +n^2$的和才是平方数

附上代码

#pragma GCC optimize("-Ofast","-funroll-all-loops")
#include
#define int long long
#define lowbit(x) (x &(-x))
#define endl '\n'
using namespace std;
const int INF=0x3f3f3f3f;
const int dir[4][2]={-1,0,1,0,0,-1,0,1};
const double PI=acos(-1.0);
const double e=exp(1.0);
const double eps=1e-10;
const int M=1e9+7;
const int N=2e5+10;
typedef long long ll;
typedef pair<int,int> PII;
typedef unsigned long long ull;
signed main(){
	ios::sync_with_stdio(false);
	cin.tie(0);cout.tie(0);

	int t;
	cin>>t;
	while(t--){
		int n;
		cin>>n;
		if(n==1||n==24) cout<<"Fake news!"<<endl;
		else cout<<"Nobody knows it better than me!"<<endl;
	}
	return 0;
}