oj.uz

답안 #153218

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
153218 2019-09-13T01:13:39 Z gs18103 먼 별 (KOI16_dist) C++14
42 / 100
 2000 ms 2752 KB 
#include <bits/stdc++.h>
#define x first
#define y second
#define all(v) v.begin(), v.end()
 
using namespace std;
typedef long long ll;
typedef pair <ll, ll> pll;
 
ll arr[30303][4];
pll base;
int n, T;

ll ccw(pll a, pll b, pll c) {
	return (b.x-a.x)*(c.y-a.y)-(b.y-a.y)*(c.x-a.x);
}

ll dis(pll a, pll b) {
	return (a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y);
}

ll cal_dis(int t) {
	vector <pll> p, ch;
	for(int i = 0; i < n; i++) {
		p.emplace_back(arr[i][0] + arr[i][2] * (ll)t, arr[i][1] + arr[i][3] * (ll)t);
	}
	sort(all(p));
	p.erase(unique(all(p)), p.end());
	base = p[0];
	sort(p.begin()+1, p.end(), [](pll a, pll b) {
		if(ccw(base, a, b) == 0) return dis(base, a) < dis(base, b);
		return ccw(base, a, b) > 0;
	});
	ch.push_back(base);
	for(int i = 1; i < p.size(); i++) {
		while(ch.size() >= 2) {
			pll p1 = ch[ch.size()-2], p2 = ch[ch.size()-1];
			if(ccw(p1, p2, p[i]) > 0) break;
			ch.pop_back();
		}
		ch.push_back(p[i]);
	}

	int idx = 0;
	ll ret = 0;
	for(int i = 0; i < ch.size(); i++) {
		for(int j = 0; j < ch.size(); j++) {
			ret = max(ret, dis(ch[i], ch[j]));
		}
	}
	return ret;
}

int search(int s, int e) {
	if(s + 10 >= e) 	{
		ll dis = 9000000000000000000LL;
		for(int i = s; i <= e; i++) {
			dis = min(dis, cal_dis(i));
		}
		for(int i = s; i <= e; i++) {
			if(dis == cal_dis(i)) return i;
		}
	}
	int t1 = (2 * s + e) / 3, t2 = (s + 2 * e) / 3;
	ll dis1 = cal_dis(t1), dis2 = cal_dis(t2);
	if(dis1 <= dis2) return search(s, t2);
	else return search(t1, e);
}
 
int main() {
	ios::sync_with_stdio(false); cin.tie(0);
	cin >> n >> T;
	for(int i = 0; i < n; i++) {
		for(int j = 0; j < 4; j++) {
			cin >> arr[i][j];
		}
	}
	int ans = search(0, T);
	cout << ans << '\n' << cal_dis(ans);
}

Compilation message

dist.cpp: In function 'll cal_dis(int)':
dist.cpp:35:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 1; i < p.size(); i++) {
                 ~~^~~~~~~~~~
dist.cpp:46:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < ch.size(); i++) {
                 ~~^~~~~~~~~~~
dist.cpp:47:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j = 0; j < ch.size(); j++) {
                  ~~^~~~~~~~~~~
dist.cpp:44:6: warning: unused variable 'idx' [-Wunused-variable]
  int idx = 0;
      ^~~

Subtask #1
2.0 / 2.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 380 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
5 Correct 2 ms 376 KB Output is correct
6 Correct 2 ms 376 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
8 Correct 2 ms 376 KB Output is correct
9 Correct 2 ms 376 KB Output is correct
10 Correct 2 ms 376 KB Output is correct

Subtask #2
40.0 / 40.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 380 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
5 Correct 2 ms 376 KB Output is correct
6 Correct 2 ms 376 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
8 Correct 2 ms 376 KB Output is correct
9 Correct 2 ms 376 KB Output is correct
10 Correct 2 ms 376 KB Output is correct
11 Correct 16 ms 380 KB Output is correct
12 Correct 38 ms 504 KB Output is correct
13 Correct 15 ms 376 KB Output is correct
14 Correct 18 ms 376 KB Output is correct
15 Correct 11 ms 376 KB Output is correct
16 Correct 62 ms 632 KB Output is correct
17 Correct 11 ms 504 KB Output is correct
18 Correct 5 ms 376 KB Output is correct
19 Correct 13 ms 376 KB Output is correct
20 Correct 16 ms 376 KB Output is correct

Subtask #3
0 / 39.0

# 결과 실행 시간 메모리 Grader output
1 Correct 213 ms 2456 KB Output is correct
2 Correct 158 ms 2400 KB Output is correct
3 Correct 166 ms 2308 KB Output is correct
4 Execution timed out 2021 ms 2752 KB Time limit exceeded
5 Halted 0 ms 0 KB -

Subtask #4
0 / 19.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 380 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
5 Correct 2 ms 376 KB Output is correct
6 Correct 2 ms 376 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
8 Correct 2 ms 376 KB Output is correct
9 Correct 2 ms 376 KB Output is correct
10 Correct 2 ms 376 KB Output is correct
11 Correct 16 ms 380 KB Output is correct
12 Correct 38 ms 504 KB Output is correct
13 Correct 15 ms 376 KB Output is correct
14 Correct 18 ms 376 KB Output is correct
15 Correct 11 ms 376 KB Output is correct
16 Correct 62 ms 632 KB Output is correct
17 Correct 11 ms 504 KB Output is correct
18 Correct 5 ms 376 KB Output is correct
19 Correct 13 ms 376 KB Output is correct
20 Correct 16 ms 376 KB Output is correct
21 Correct 213 ms 2456 KB Output is correct
22 Correct 158 ms 2400 KB Output is correct
23 Correct 166 ms 2308 KB Output is correct
24 Execution timed out 2021 ms 2752 KB Time limit exceeded
25 Halted 0 ms 0 KB -