1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
| #include <bits/stdc++.h>
#define int long long
#define double long double
#define pii pair<int, int>
#define N 10000
#define x first
#define y second
#define IOS ios::sync_with_stdio(0),cin.tie(0)
using namespace std;
struct pt{
int x,y;
bool operator == (pt b){
if(x == b.x && y == b.y)return true;
return false;
}
pt operator - (pt b){return {x - b.x , y - b.y};}
pt operator + (pt b){return {x + b.x , y + b.y};}
int operator ^ (pt b){return (x * b.y - y * b.x);}
int operator * (pt b){return (x * b.x + y * b.y);}
};
bool onseg(pt a,pt b,pt o){
int cross = (a - o) ^ (b - o);
int dot = (a - o) * (b - o);
return cross == 0 && dot <= 0;
}
int dir(pt a,pt b,pt o){
int cross = (a - o) ^ (b - o);
if(cross == 0)return 0;
else if(cross > 0)return 1;
else return -1;
}
bool inter(pt a,pt b,pt c,pt d){
if(onseg(a,b,c) || onseg(a,b,d))return true;
if(onseg(c,d,a) || onseg(c,d,b))return true;
if((dir(a,b,c) * dir(a,b,d)) == -1
&& (dir(c,d,a) * dir(c,d,b)) == -1)
return true;
return false;
}
signed main(){
IOS;
int t;cin>>t;
while(t--){
pt pot[4];
for(int i=0;i<4;i++)cin>>pot[i].x>>pot[i].y;
if(inter(pot[0],pot[1],pot[2],pot[3]))cout<<"YES"<<"\n";
else cout<<"NO"<<"\n";
}
}
|