真要气死了，赛时快要做出来了现在还没a，这题太几把毒瘤了

公式我稍微变了一下形，应该是没问题的

#include<iostream>
#include<cmath>
#define int long long
using namespace std;
int n,k,a;
long double t,dbs,p;
signed main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	cin>>n>>k;
	for(int i=1;i<=n;i++) cin>>a,t+=a,dbs+=a*a;
	t/=n;
	p=dbs/n-t*t;
	if(!p){
		cout<<"No answer!";
		return 0;
	}
	else{
		long double d=k/p;
		int t=sqrt(d);
        if(!t) cout<<1;
        else if(abs(p*t*t-k)<=abs(p*(t+1)*(t+1)-k)) cout<<t;
        else cout<<t+1;
	}
	return 0;
}

wrong answer On line 1 column 9, read 8, expected 9.