Plants vs. Zombies

Time Limit: 2000/1000ms (Java/Others)

Problem Description:

There is a zombie on your lawn,There is a zombie on your lawn,There are many zombies on your lawn,So can you defeat them?You have many plants that can kill the zombie in a hit and your plants can kill all zombies on their straight shooting path.

Input:

The input consists of several cases.The first line are two positive integer n,m,indicating the number of plants and zombies.Then the next n lines show the line (ax+by+c==0) of plants in the form of (a,b,c),Then the last lines show the positions of zombies in the form of (xi,yi).All input data is a 32-bit integer.

Output:

Print "duang" if you can kill all zombies,else print "eat your brain".

Sample Input:

2 2

1 1 1

1 2 3

1 -2 -1 0

Sample Output:

duang
解题思路：简单判断m个坐标是否都满足n个方程ax+by+c==0中的任意一个，如果都满足，则输出"duang"，否则输出"eat your brain"，水过！
AC代码：

 #include<bits/stdc++.h>

 using namespace std;

 const int maxn = 1e6+;//开大一点

 int n,m,num,x,y,a[maxn],b[maxn],c[maxn];

 int main(){

     while(~scanf("%d%d",&n,&m)){

         for(int i=;i<n;++i)scanf("%d%d%d",&a[i],&b[i],&c[i]);

         num=;

         for(int j=;j<m;++j){

             scanf("%d%d",&x,&y);

             for(int i=;i<n;++i)

                 if(a[i]*x+b[i]*y+c[i]==){num++;break;}

         }

         if(num!=m)printf("eat your brain\n");

         else printf("duang\n");

     }

     return ;

 }