답안 #120375

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
120375 2019-06-24T09:27:11 Z tmwilliamlin168 Printed Circuit Board (CEOI12_circuit) C++14
10 / 100
17 ms 4676 KB
#include <bits/stdc++.h>
using namespace std;

int in() {
	char c=0;
	while(c<'0'||c>'9')
		c=getchar_unlocked();
	int r=0;
	while(c>='0'&&c<='9') {
		r=r*10+c-'0';
		c=getchar_unlocked();
	}
	return r;
}

void out(int x) {
	int c=0, r=0;
	for(; x%10==0; ++c, x/=10);
	for(; x; r=r*10+x%10, x/=10);
	for(; r; r/=10)
		putchar_unlocked('0'+r%10);
	while(c--)
		putchar_unlocked(' ');
}

const int mxN=2e5;
int n, l, r;
long long x[mxN+1], y[mxN+1];
vector<int> v, s;
bool b[mxN];

int main() {
	auto cp=[](int a, int b, int c) {
		return (y[c]-y[a])*(x[b]-x[a])-(y[b]-y[a])*(x[c]-x[a]);
	};
	n=in();
	for(int i=0; i<n; ++i) {
		x[i]=in(), y[i]=in();
		if(!i||cp(n, l, i)>0||!cp(n, l, i)&&x[i]<x[l])
			l=i;
		if(!i||cp(n, r, i)<0||!cp(n, r, i)&&x[i]<x[r])
			r=i;
	}
	int ic=cp((l+n-1)%n, l, (l+1)%n)>0?1:n-1;
	for(; l^r; l=(l+ic)%n)
		v.push_back(l);
	v.push_back(r);
	s={0, 1};
	for(int i=2; i<v.size(); ++i) {
		auto ul=[&]() {
			while(cp(n, v[s.back()], v[i])>=0&&cp(v[i-1], v[i], v[s.back()])<=0)
				s.pop_back();
			for(int j=i, c=cp(n, v[s.back()], v[i])<0; cp(n, v[s.back()], v[i])>=0||!c; ++i) {
				if(i^j?cp(n, v[j], v[i])>=0&&cp(n, v[j], v[i+1])<0&&cp(v[i], v[i+1], v[j])>0:cp(n, v[i], v[i+1])<0&&cp(v[i-1], v[i], v[i+1])>0)
					++c;
				if(cp(n, v[j], v[i])<0&&cp(n, v[j], v[i+1])>=0&&cp(v[i], v[i+1], v[j])<0)
					--c;
			}
		};
		if(!cp(n, v[i-1], v[i])&&(cp(n, v[i-2], v[i-1])<0)==(cp(v[i-2], v[i-1], v[i])<0))
			s.pop_back();
		else if(cp(n, v[i-1], v[i])<=0&&cp(n, v[i-2], v[i-1])>0&&cp(v[i-2], v[i-1], v[i])<0) {
			while(cp(n, v[s.back()], v[i])<=0)
				++i;
			s.pop_back();
			ul();
		} else if(cp(n, v[i-1], v[i])>0&&(cp(n, v[i-2], v[i-1])>=0||cp(v[i-2], v[i-1], v[i])<0))
			ul();
		else if(cp(n, v[i-1], v[i])>=0)
			while(cp(n, v[s.back()], v[i])>=0)
				++i;
		s.push_back(i);
	}
	out(s.size());
	putchar_unlocked('\n');
	for(int a : s)
		b[v[a]]=1;
	for(int i=0; i<n; ++i) {
		if(b[i]) {
			out(i+1);
			putchar_unlocked(' ');
		}
	}
}

Compilation message

circuit.cpp: In function 'int main()':
circuit.cpp:39:37: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   if(!i||cp(n, l, i)>0||!cp(n, l, i)&&x[i]<x[l])
                         ~~~~~~~~~~~~^~~~~~~~~~~
circuit.cpp:41:37: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   if(!i||cp(n, r, i)<0||!cp(n, r, i)&&x[i]<x[r])
                         ~~~~~~~~~~~~^~~~~~~~~~~
circuit.cpp:49:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=2; i<v.size(); ++i) {
               ~^~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Incorrect 2 ms 384 KB Output isn't correct
2 Incorrect 2 ms 384 KB Output isn't correct
3 Incorrect 2 ms 512 KB Output isn't correct
4 Incorrect 3 ms 512 KB Output isn't correct
5 Incorrect 2 ms 640 KB Output isn't correct
6 Incorrect 2 ms 640 KB Output isn't correct
7 Incorrect 3 ms 768 KB Output isn't correct
8 Correct 2 ms 512 KB Output is correct
9 Incorrect 3 ms 640 KB Output isn't correct
10 Incorrect 3 ms 640 KB Output isn't correct
11 Correct 3 ms 640 KB Output is correct
12 Incorrect 3 ms 896 KB Output isn't correct
13 Incorrect 4 ms 1024 KB Output isn't correct
14 Incorrect 4 ms 1280 KB Output isn't correct
15 Incorrect 5 ms 1536 KB Output isn't correct
16 Incorrect 8 ms 2556 KB Output isn't correct
17 Incorrect 9 ms 2352 KB Output isn't correct
18 Incorrect 14 ms 4600 KB Output isn't correct
19 Incorrect 15 ms 4600 KB Output isn't correct
20 Incorrect 17 ms 4676 KB Output isn't correct