Submission #153200

# Submission time Handle Problem Language Result Execution time Memory
153200 2019-09-12T21:10:33 Z gs18103 None (KOI16_dist) C++14
42 / 100
2000 ms 2216 KB
#include <bits/stdc++.h>
#define x first
#define y second
 
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] * t, arr[i][1] + arr[i][3] * t);
	}
	sort(p.begin(), 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 < 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 < p.size(); i++) {
		for(int j = 0; j < p.size(); j++) {
			ret = max(ret, dis(p[i], p[j]));
		}
	}
	return ret;
}

int search(int s, int e) {
	if(s + 10 >= e) 	{
		ll dis = 7000000000000000000LL;
		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:44:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < p.size(); i++) {
                 ~~^~~~~~~~~~
dist.cpp:45:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j = 0; j < p.size(); j++) {
                  ~~^~~~~~~~~~
dist.cpp:42:6: warning: unused variable 'idx' [-Wunused-variable]
  int idx = 0;
      ^~~
# Verdict Execution time Memory 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 420 KB Output is correct
10 Correct 2 ms 376 KB Output is correct
# Verdict Execution time Memory 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 420 KB Output is correct
10 Correct 2 ms 376 KB Output is correct
11 Correct 135 ms 452 KB Output is correct
12 Correct 135 ms 516 KB Output is correct
13 Correct 125 ms 448 KB Output is correct
14 Correct 137 ms 376 KB Output is correct
15 Correct 129 ms 376 KB Output is correct
16 Correct 126 ms 376 KB Output is correct
17 Correct 127 ms 504 KB Output is correct
18 Correct 131 ms 472 KB Output is correct
19 Correct 102 ms 504 KB Output is correct
20 Correct 135 ms 508 KB Output is correct
# Verdict Execution time Memory Grader output
1 Execution timed out 2044 ms 2216 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory 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 420 KB Output is correct
10 Correct 2 ms 376 KB Output is correct
11 Correct 135 ms 452 KB Output is correct
12 Correct 135 ms 516 KB Output is correct
13 Correct 125 ms 448 KB Output is correct
14 Correct 137 ms 376 KB Output is correct
15 Correct 129 ms 376 KB Output is correct
16 Correct 126 ms 376 KB Output is correct
17 Correct 127 ms 504 KB Output is correct
18 Correct 131 ms 472 KB Output is correct
19 Correct 102 ms 504 KB Output is correct
20 Correct 135 ms 508 KB Output is correct
21 Execution timed out 2044 ms 2216 KB Time limit exceeded
22 Halted 0 ms 0 KB -