답안 #68891

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
68891 2018-08-19T07:12:37 Z ainta Printed Circuit Board (CEOI12_circuit) C++17
85 / 100
100 ms 31132 KB
#include<stdio.h>
#include<algorithm>
using namespace std;
struct point {
	long long x, y;
	int c;
	bool operator <(const point &p)const {
		return x*p.y != y*p.x ? x*p.y<y*p.x : x<p.x;
	}
}w[200001];
struct point2 {
	int x, y;
}P[200001];
struct vector2 {
	double x, y;
	int c;
}w2[200001], t1, t2, t3;
double X1, X2, Y1, Y2, tt;
int r[400001], N, i, c, sz, IT2[600001];
bool v[400001];
double IT[600001], INF = 1e9;
double F(double x, double y) {
	tt = (Y2*x - X2*y) / ((X1 - X2)*y - (Y1 - Y2)*x);
	return Y1*tt + Y2*(1 - tt);
}
bool ccw() {
	return (t2.x - t1.x)*(t3.y - t1.y) - (t2.y - t1.y)*(t3.x - t1.x)<0;
}
void Do(int b, int e, int k) {
	int s = b - sz, l = e - sz, t = 1;
	double tp;
	if (k == 8999) {
		k = k;
	}
	while (b <= e) {
		if (b & 1) {
			tp = F(w2[s].x, w2[s].y);
			if (tp<IT[b])IT[b] = tp, IT2[b] = k;
			else if (tp == IT[b]) {
				t1.y = tp; t1.x = tp*(double)w2[s].x / w2[s].y;
				t2.x = P[IT2[b]].x, t2.y = P[IT2[b]].y;
				if (t1.y != P[k].y)t3.x = P[k].x, t3.y = P[k].y;
				else t3.x = P[k + 1].x, t3.y = P[k + 1].y;
				if (ccw())IT2[b] = k;
			}
		}
		if (!(e & 1)) {
			tp = F(w2[l - t + 1].x, w2[l - t + 1].y);
			if (tp<IT[e])IT[e] = tp, IT2[e] = i;
			else if (tp == IT[e]) {
				t1.y = tp; t1.x = tp*(double)w2[l - t + 1].x / w2[l - t + 1].y;
				t2.x = P[IT2[e]].x, t2.y = P[IT2[e]].y;
				if (t1.y != P[k].y)t3.x = P[k].x, t3.y = P[k].y;
				else t3.x = P[k + 1].x, t3.y = P[k + 1].y;
				if (ccw())IT2[e] = k;
			}
		}
		if (b & 1)s += t;
		if (!(e & 1))l -= t;
		t <<= 1;
		b = (b + 1) >> 1, e = (e - 1) >> 1;
	}
}
void DFS(int s, int z, int a, int b) {
	int tt = s;
	if (s >= c)return;
	if (s == 0) {
		if (a >= sz)return;
		tt = 1;
	}
	if (b == -1 && IT[a] != INF)b = IT2[a];
	else if (IT[a] != INF) {
		X1 = P[b].x, X2 = P[b + 1].x, Y1 = P[b].y, Y2 = P[b + 1].y;
		if (F(w2[tt].x, w2[tt].y)>IT[a])b = IT2[a];
	}
	if (a >= sz) {
		if (a - sz >= 1 && a - sz<c)IT2[a] = b;
		return;
	}
	DFS(s, z >> 1, a << 1, b);
	DFS(s + z, z >> 1, (a << 1) + 1, b);
}
bool Pos(int a) {
	if (abs(a) == N - 1)return true;
	return a<0 ? false : a>1 ? false : true;
}
int main()
{
	scanf("%d", &N);
	for (i = 0; i<N; i++) {
		scanf("%d%d", &P[i].x, &P[i].y);
		w[i].x = P[i].x, w[i].y = P[i].y, w[i].c = i;
	}
	P[N] = P[0];
	sort(w, w + N);
	for (i = 0; i<N; i++) {
		c++;
		if (i && w[i].x*w[i - 1].y == w[i].y*w[i - 1].x)c--;
		else w2[c].x = w[i].x, w2[c].y = w[i].y, w2[c].c = w[i].c;
		r[w[i].c] = c;
	}
	r[N] = r[0];
	sz = 1;
	while (sz <= c)sz *= 2;
	for (i = 1; i<sz * 2; i++)IT[i] = INF;
	for (i = 0; i<N; i++) {
		if (r[i] == r[i + 1])continue;
		X1 = P[i].x, Y1 = P[i].y, X2 = P[i + 1].x, Y2 = P[i + 1].y;
		Do(sz + min(r[i], r[i + 1]), sz + max(r[i], r[i + 1]) - 1, i);
	}
	DFS(0, sz >> 1, 1, -1);
	v[w2[1].c] = v[w2[c].c] = true;
	for (i = 1; i<c - 1; i++) {
		if (Pos(w2[i + 1].c - IT2[sz + i]) || Pos(w2[i + 1].c - IT2[sz + i + 1]))v[w2[i + 1].c] = true;
	}
	c = 0;
	for (i = 0; i<N; i++) {
		if (v[i])c++;
	}
	printf("%d\n", c);
	for (i = 0; i<N; i++)if (v[i])printf("%d ", i + 1);
}

Compilation message

circuit.cpp: In function 'int main()':
circuit.cpp:89:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &N);
  ~~~~~^~~~~~~~~~
circuit.cpp:91:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d", &P[i].x, &P[i].y);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 3 ms 624 KB Output is correct
3 Correct 4 ms 860 KB Output is correct
4 Correct 5 ms 1004 KB Output is correct
5 Correct 9 ms 1796 KB Output is correct
6 Correct 9 ms 1880 KB Output is correct
7 Correct 19 ms 3164 KB Output is correct
8 Correct 8 ms 3164 KB Output is correct
9 Correct 8 ms 3164 KB Output is correct
10 Correct 9 ms 3164 KB Output is correct
11 Correct 10 ms 3164 KB Output is correct
12 Correct 16 ms 3908 KB Output is correct
13 Correct 21 ms 4888 KB Output is correct
14 Correct 24 ms 6560 KB Output is correct
15 Correct 25 ms 7812 KB Output is correct
16 Correct 59 ms 13520 KB Output is correct
17 Correct 89 ms 14752 KB Output is correct
18 Execution timed out 104 ms 25920 KB Time limit exceeded
19 Execution timed out 111 ms 28396 KB Time limit exceeded
20 Execution timed out 160 ms 31132 KB Time limit exceeded