oj.uz

답안 #153213

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
153213 2019-09-13T00:32:23 Z gs18103 먼 별 (KOI16_dist) C++14
2 / 100
 198 ms 2412 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(), 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();
		}
		if(p[i] != base) 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 376 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 376 KB Output is correct
11 Correct 16 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 Incorrect 198 ms 2412 KB Output isn't correct
2 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 376 KB Output is correct
11 Correct 16 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 -