一直以为小图灵数据太强，没想到是我太弱。输出打错，痛失40分。

#include <bits/stdc++.h>
using namespace std;
long long t,m,a[5001],b[5001],c[5001],ans[5001],j,d[5001];
bool vis[5001];
int main(){
	freopen("uqe.in","r",stdin);
	freopen("uqe.out","w",stdout);
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin>>t>>m;
	while(t--){
		j++;
		cin>>a[j]>>b[j]>>c[j];
		d[j]=b[j]*b[j]-4*a[j]*c[j];
		if(d[j]<0) vis[j]=1;
		else ans[j]=max((-1*b[j]+sqrt(d[j]))/(2*a[j]),(-1*b[j]-sqrt(d[j]))/(2*a[j]));
	}
	for(int i = 1 ; i<=j ; i++){
		if(vis[i]==0) cout<<ans[j]<<endl;
		else cout<<"NO"<<endl;
	}
	return 0;
}