oj.uz

답안 #153215

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
153215 2019-09-13T00:35:14 Z gs18103 먼 별 (KOI16_dist) C++14
2 / 100
 2000 ms 2724 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) {
		return ccw(base, a, b) > 0;
	});
	ch.push_back(base);
	for(int i = 1; i < n; 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:45:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < ch.size(); i++) {
                 ~~^~~~~~~~~~~
dist.cpp:46:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j = 0; j < ch.size(); j++) {
                  ~~^~~~~~~~~~~
dist.cpp:43:6: 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 376 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 380 KB Output is correct

Subtask #2
0 / 40.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 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 380 KB Output is correct
11 Correct 15 ms 376 KB Output is correct
12 Correct 37 ms 504 KB Output is correct
13 Correct 13 ms 376 KB Output is correct
14 Correct 16 ms 376 KB Output is correct
15 Incorrect 9 ms 376 KB Output isn't correct
16 Halted 0 ms 0 KB -

Subtask #3
0 / 39.0

# 결과 실행 시간 메모리 Grader output
1 Correct 202 ms 2408 KB Output is correct
2 Correct 151 ms 2400 KB Output is correct
3 Correct 155 ms 2304 KB Output is correct
4 Execution timed out 2058 ms 2724 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 376 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 380 KB Output is correct
11 Correct 15 ms 376 KB Output is correct
12 Correct 37 ms 504 KB Output is correct
13 Correct 13 ms 376 KB Output is correct
14 Correct 16 ms 376 KB Output is correct
15 Incorrect 9 ms 376 KB Output isn't correct
16 Halted 0 ms 0 KB -