计蒜客 28317.Growling Gears-一元二次方程的顶点公式 (Benelux Algorithm Programming Contest 2014 Final ACM-ICPC Asia Training League 暑假第一阶段第二场 G)

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 #include<cmath>
 5 #include<cstdlib>
 6 #include<queue>
 7 #include<map>
 8 #include<algorithm>
 9 using namespace std;
10 typedef long long ll;
11 const int maxn=1e5+10;
12 int main(){
13     int t;scanf("%d",&t);
14     while(t--){
15         int n;scanf("%d",&n);
16         int a,b,c;
17         ll maxx=-1;int ans;
18         for(int i=1;i<=n;i++){
19             scanf("%d%d%d",&a,&b,&c);
20             ll cnt=(4*a*c*(-1)-b*b)/(4*a*(-1));
21             if(maxx<=cnt){
22                 maxx=cnt;
23                 ans=i;
24             }
25         }
26         printf("%d
",ans);
27     }
28     return 0;
29 }