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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#672020#5067. Two WallsmobbbWA 0ms3672kbC++205.2kb2024-10-24 15:22:122024-10-24 15:22:12

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你现在查看的是最新测评结果

  • [2024-10-24 15:22:12]
  • 评测
  • 测评结果:WA
  • 用时:0ms
  • 内存:3672kb
  • [2024-10-24 15:22:12]
  • 提交

answer

#include <bits/stdc++.h>

#define ll long long

#define db ll
constexpr db EPS = 0;
int sign(db a){ return a < -EPS ? -1 : a > EPS; }
int cmp(db a,db b) {return sign(a - b);}
struct P {
	db x,y;
	P() {}
	P(db _x,db _y) : x(_x),y(_y){}
	P operator+(P p) {return {x + p.x,y + p.y};}
	P operator-(P p) {return {x - p.x,y - p.y};}
	P operator*(db d) {return {x * d,y * d};}
	P operator/(db d) {return {x / d,y / d};}
	
	bool operator < (P p) const{
		int c = cmp(x,p.x);
		if (c) return c == -1;
		return cmp(y , p.y) == -1;
	}

	bool operator == (P o) const{
		return cmp(x,o.x) == 0 && cmp(y,o.y) == 0;
	}
	db dot(P p){return x * p.x + y * p.y;}
	// a * b == |a| * |b| * cos<a,b>  ,大于0为锐角小于0为钝角等于0为直角
	db det(P p){return {x * p.y - y * p.x};} 
	// a * b == |a| * |b| * sin<a,b> == - (b * a) ,a逆时针转多少度可以转到b
	// 大于0 b在a的逆时针方向,等于0共线,小于0 b在a的顺时针方向
	void read(){std::cin >> x >> y;}
	void print(){std::cout << x << " " << y  << "\n";}
	db distTo(P p) {return (*this - p).abs();}
	db alpha() {return atan2l(y,x);}
	db abs() {return sqrtl(abs2());}
	db abs2() {return x * x + y * y;}
	P rot90() {return P(-y,x);} // 逆时针旋转90度
	int quad(){return sign(y) == 1 || (sign(y) == 0 && sign(x) == 1);}
	P unit() {return *this / abs();}
	// P rot(db an){return {x * cosl(an) - y * sinl(an),x * sinl(an) + y * cosl(an)};}
};
#define cross(p1,p2,p3) ((p2.x - p1.x) * (p3.y - p1.y) - (p2.y - p1.y) * (p3.x - p1.x))
#define crossOp(p1,p2,p3) sign(cross(p1,p2,p3)) // 以p1为起点去考虑<p1,p2> <p1,p3> 
// 大于p2在p3的逆时针方向,小于0在顺时针,等于0共线

// 两个直线是否相交
bool chkLL(P p1,P p2,P q1,P q2){
	db a1 = cross(q1,q2,p1),a2 = -cross(q1,q2,p2);
	return sign(a1 + a2) != 0;
}
// 求两直线交点
P isLL(P p1,P p2,P q1,P q2){
	db a1 = cross(q1,q2,p1),a2 = -cross(q1,q2,p2);
	return (p1 * a2 + p2 * a1) / (a1 + a2);
}
// 判断区间 [l1,r1] ,[l2,r2] 是否相交
bool intersect(db l1,db r1,db l2,db r2){
	if (l1 > r1) std::swap(l1,r1);if (l2 > r2) std::swap(l2,r2);
	return !(cmp(r1,l2) == -1 || cmp(r2,l1) == -1);
}
// 两线段是否相交
bool isSS(P p1,P p2,P q1,P q2){
	return intersect(p1.x,p2.x,q1.x,q2.x) && intersect(p1.y,p2.y,q1.y,q2.y) && 
	crossOp(p1,p2,q1) * crossOp(p1,p2,q2) <= 0 && crossOp(q1,q2,p1) * crossOp(q1,q2,p2) <= 0;
}
// 两线段是否严格相交
bool isSS_strict(P p1,P p2,P q1,P q2){
	return crossOp(p1,p2,q1) * crossOp(p1,p2,q2) < 0 && crossOp(q1,q2,p1) * crossOp(q1,q2,p2) < 0;
}
// m 在不在a和b之间
bool isMiddle(db a,db m,db b){
	return sign(a - m) == 0 || sign(b - m) == 0 || (a < m != b < m);
}
// 点m 在不在a和b之间
bool isMiddle(P a,P m,P b){
	return isMiddle(a.x,m.x,b.x) && isMiddle(a.y,m.y,b.y);
}
// 点q在线段上
bool onSeg(P p1,P p2, P q){
	return crossOp(p1,p2,q) == 0 && isMiddle(p1,q,p2);
}
// 点q严格在线段上
bool onSeg_strict(P p1,P p2,P q){
	return crossOp(p1,p2,q) == 0 && sign((q - p1).dot(p1 - p2)) * sign((q - p2).dot(p1 - p2));
}
// 求 q 到 p1p2的投影
P proj(P p1,P p2,P q){
	P dir = p2 - p1;
	return p1 + dir * (dir.dot(q - p1) / dir.abs2());
}
// 求 q以直线p1p2为轴的反射
P refect(P p1,P p2,P q){
	return proj(p1,p2,q) * 2 - q;
}
// 求q到线段p1p2的最短距离
db nearest(P p1,P p2,P q){
	if (p1 == p2) return p1.distTo(q);
	P h = proj(p1,p2,q);
	if (isMiddle(p1,h,p2)){
		return q.distTo(h);
	}
	return std::min(p1.distTo(q),p2.distTo(q));
}
// 求线段p1p2 与线段q1q2的距离
db disSS(P p1,P p2,P q1,P q2){
	if(isSS(p1,p2,q2,q2)) return 0;
	return std::min({nearest(p1,p2,q1),nearest(p1,p2,q2),nearest(q1,q2,p1),nearest(q1,q2,p2)});
}
// 极角排序
// sort(p,p + n,[&](P a,P b){
// 	int qa = a.quad,qb = b.quad;
// 	if (qa != qb) return qa < qb;
// 	return sign(a.det(b)) > 0;
// })

int solve(){
	P a,b,c,d,e,f;
	a.read(),b.read();
	c.read(),d.read();
	e.read(),f.read();
	if (!isSS(a,b,c,d) && !isSS(a,b,e,f)){
		return 0;
	}
	if (!isSS_strict(c,d,e,f)){
		return 1;
	}
	if (crossOp(c,d,a) * crossOp(c,d,b) >= 0) {
		return 1;
	}
	if (crossOp(e,f,a) * crossOp(e,f,b) >= 0){
		return 1;
	}
	if (crossOp(e,f,a) >= 0) {
		std::swap(e,f);
	}
	if (crossOp(d,c,a) <= 0){
		std::swap(c,d);
	}
	if ((c - d).det(f - e) <= 0){
		std::swap(c,f);
		std::swap(d,e);
	}

	P la = d - a,ra = e - a;
	P lb = c - b,rb = f - b;
	std::vector<std::pair<P,int>> evt;
	evt.push_back({la,1});
	evt.push_back({ra,-1});
	evt.push_back({lb,1});
	evt.push_back({rb,-1});

	int cur = (ra.y < 0 && la.y > 0) + (rb.y < 0 && lb.y > 0);
	sort(evt.begin(),evt.end(),[&](std::pair<P,int> a,std::pair<P,int> b){
		int qa = a.first.quad(),qb = b.first.quad();
		if (qa != qb) return qa < qb;
		if (sign(a.first.det(b.first)) == 0){
			return a.second < b.second;
		}
		return sign(a.first.det(b.first)) > 0;
	});
	if (cur >= 0) return 1;
	for (auto [a,b] : evt){
		cur += b;
		if (cur >= 2){
			return 1;
		}
	}
	return 2;
}

int main(){
	std::ios::sync_with_stdio(false);
	std::cin.tie(nullptr);

	int t;
	
	std::cin >> t;

	while (t--){
		std::cout << solve() << '\n';
	}

	return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 0ms
memory: 3672kb

input:

3
0 0
1 1
2 2 3 3
4 4 5 5
0 0
1 1
2 2 3 3
2 2 3 3
0 0
10 10
10 0 0 10
1 1 2 2

output:

0
0
1

result:

ok 3 number(s): "0 0 1"

Test #2:

score: -100
Wrong Answer
time: 0ms
memory: 3512kb

input:

2
-999999999 999999998
999999999 999999998
-1000000000 -1000000000 1000000000 1000000000
1000000000 -1000000000 -1000000000 1000000000
-999999999 999999998
999999999 999999998
-999999998 -999999998 1000000000 1000000000
999999998 -999999998 -1000000000 1000000000

output:

1
1

result:

wrong answer 1st numbers differ - expected: '2', found: '1'