Fight Against Monsters Gym - 102222H【贪心】

贪心的策略

 #include <bits/stdc++.h>
 using namespace std;
 const int N=1e5+;
 typedef long long ll;
 struct m
 {
     int hp,atk,num;
 }mon[N];
 bool cmp(m a,m b)
 {
     return a.atk*b.num>b.atk*a.num;//排序的依据是被攻击的次数和攻击力的乘积
 }
 int n;
 int main()
 {
     int t,cas=;
     scanf("%d",&t);
     while(t--)
     {
         scanf("%d",&n);
         ll ack=,ans=;
         for(int i=;i<=n;i++)
         {
             scanf("%d%d",&mon[i].hp,&mon[i].atk);
             ack+=mon[i].atk;
             int t=(int)sqrt(mon[i].hp*2.0)-;
             while((t+)*t/<mon[i].hp)
                 t++;
             mon[i].num=t;
         }
         sort(mon+,mon++n,cmp);
         for(int i=;i<=n;i++)
         {
             ans+=(mon[i].num*ack);
             ack-=mon[i].atk;
         }
         printf("Case #%d: %lld\n",++cas,ans);
     }
     return ;
 }