题意:给你2个点A和B,和n条直线(ax+by+c=0),给n个a,b,c,求A到B至少跨过多少条直线

题解:对于每条直线,看2个点是否在他同侧,异侧答案就+1

1 #include
     
       2 using namespace std; 3 double x1,x2,y11,y2,a,b,c,t1,t2;  4 int n,ans; 5 int main() 6 { 7     cin>>x1>>y11; 8     cin>>x2>>y2; 9     scanf("%d",&n);10     for(int i=0;i
      
       >a>>b>>c;13         t1=a*x1+b*y11+c;14         t2=a*x2+b*y2+c;15         if (t1*t2<0) ans++;16     }17     cout<
       
        <