卡70分就是wa3个点

#include<iostream>
#include<cstdio>
#include<cmath>
using namespace std;
long long k,n,e,d;
int main()
{
//	freopen("decode.in","r",stdin);
//	freopen("decode.out","w",stdout);
	cin>>k;
	while(k--)
	{
		cin>>n>>e>>d;
		long long m=n-e*d+2;
		double x=(m-sqrt((double)m*m-4*n))/2.0;
		if((long long)x!=x)
		  cout<<"NO\n";
		else cout<<(long long)x<<" "<<(long long)m-(long long)x<<endl;
	}
//	fclose(stdin);
//	fclose(stdout);
	return 0;
}

已经尝试的事:long double,abs,sqrt-,......（但好像都不是）