Submission #815783

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
815783	2023-08-08T23:11:41 Z	Mustela_Erminea	Mecho (IOI09_mecho)	C++14	73 / 100	155 ms	6520 KB

mecho

#include <iostream>
#include <vector>
#include <queue>
#define pii pair<int, int>

using namespace std;

int N, S;
int mR, mC, dR, dC;
char grid[801][801];
int minHiveDist[801][801], minBearDist[801][801];

const int dx[4] = { -1, 1, 0, 0 };
const int dy[4] = { 0, 0, -1, 1 };
bool isValid(int r, int c) { return 0 <= r && r < N && 0 <= c && c < N; }

vector<vector<bool>> visited;
void bfs(vector<pii> initialCoords, int minDist[801][801]) {
	queue<pair<pii, int>> q; 
	visited.clear(); visited.resize(N, vector<bool>(N));
	for (pii p : initialCoords) {
		q.push({ p, 0 }); visited[p.first][p.second] = true;
	}
	while (!q.empty()) {
		pii loc = q.front().first; int dist = q.front().second; q.pop();
		minDist[loc.first][loc.second] = dist;
		for (int i = 0; i < 4; i++) {
			int r = loc.first + dx[i], c = loc.second + dy[i];
			if (isValid(r, c) && !visited[r][c] && (grid[r][c] == 'G' || grid[r][c] == 'M')) {
				visited[r][c] = true;
				q.push({ {r, c}, dist + 1 });
			}
		}
	}
}

void bfs2(int startR, int startC, int wait) {
	visited.clear(); visited.resize(N, vector<bool>(N));
	queue<pair<pii, int>> q; q.push({ {startR, startC}, 0 });
	visited[startR][startC] = true;
	while (!q.empty()) {
		pii loc = q.front().first; int dist = q.front().second; q.pop();
		minBearDist[loc.first][loc.second] = dist;
		for (int i = 0; i < 4; i++) {
			int r = loc.first + dx[i], c = loc.second + dy[i];
			if (isValid(r, c) && !visited[r][c] && (grid[r][c] == 'G' || grid[r][c] == 'M')) {
				if ((dist + 1) / S + wait < minHiveDist[r][c]) {
					visited[r][c] = true;
					q.push({ {r, c}, dist + 1 });
				}
			}
		}
	}
}
bool works(int wait) {
	bfs2(mR, mC, wait);
	for (int i = 0; i < 4; i++) {
		int r = dR + dx[i], c = dC + dy[i];
		if (isValid(r, c) && visited[r][c] && minBearDist[r][c] / S + wait < minHiveDist[r][c]) return true;
	} return false;
}

int main() {
	ios_base::sync_with_stdio(0); cin.tie(0);

	cin >> N >> S;
	for (int i = 0; i < N; i++)
		for (int j = 0; j < N; j++)
			cin >> grid[i][j];
	
	vector<pii> hives;
	for (int i = 0; i < N; i++) {
		for (int j = 0; j < N; j++) {
			if (grid[i][j] == 'H') hives.push_back({ i, j });
			if (grid[i][j] == 'M') { mR = i; mC = j; }
			if (grid[i][j] == 'D') { dR = i; dC = j; }
		}
	}

	bfs(hives, minHiveDist); minHiveDist[dR][dC] = (int)1e9;

	int low = 0, high = N * N;
	while (low < high) {
		int mid = (low + high + 1) / 2;
		if (works(mid)) low = mid;
		else high = mid - 1;
	} cout << low << endl;
}

Subtask #1

73.0 / 100.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	340 KB	Output is correct
2	Correct	0 ms	340 KB	Output is correct
3	Correct	0 ms	340 KB	Output is correct
4	Correct	0 ms	340 KB	Output is correct
5	Correct	0 ms	340 KB	Output is correct
6	Correct	0 ms	340 KB	Output is correct
7	Correct	69 ms	5028 KB	Output is correct
8	Incorrect	0 ms	340 KB	Output isn't correct
9	Correct	1 ms	340 KB	Output is correct
10	Correct	0 ms	340 KB	Output is correct
11	Correct	0 ms	340 KB	Output is correct
12	Correct	1 ms	596 KB	Output is correct
13	Incorrect	1 ms	596 KB	Output isn't correct
14	Incorrect	1 ms	596 KB	Output isn't correct
15	Correct	0 ms	340 KB	Output is correct
16	Correct	0 ms	340 KB	Output is correct
17	Correct	0 ms	340 KB	Output is correct
18	Correct	0 ms	468 KB	Output is correct
19	Correct	0 ms	468 KB	Output is correct
20	Correct	0 ms	468 KB	Output is correct
21	Correct	1 ms	468 KB	Output is correct
22	Correct	0 ms	468 KB	Output is correct
23	Correct	1 ms	468 KB	Output is correct
24	Correct	1 ms	596 KB	Output is correct
25	Correct	1 ms	596 KB	Output is correct
26	Correct	1 ms	596 KB	Output is correct
27	Correct	1 ms	596 KB	Output is correct
28	Correct	1 ms	596 KB	Output is correct
29	Correct	1 ms	596 KB	Output is correct
30	Correct	1 ms	724 KB	Output is correct
31	Correct	1 ms	596 KB	Output is correct
32	Correct	1 ms	724 KB	Output is correct
33	Correct	4 ms	2004 KB	Output is correct
34	Correct	4 ms	2260 KB	Output is correct
35	Correct	17 ms	2772 KB	Output is correct
36	Correct	5 ms	2260 KB	Output is correct
37	Correct	6 ms	2484 KB	Output is correct
38	Correct	22 ms	3200 KB	Output is correct
39	Correct	6 ms	2408 KB	Output is correct
40	Correct	7 ms	2824 KB	Output is correct
41	Correct	31 ms	3460 KB	Output is correct
42	Correct	12 ms	2876 KB	Output is correct
43	Correct	9 ms	3132 KB	Output is correct
44	Correct	37 ms	3924 KB	Output is correct
45	Correct	11 ms	2900 KB	Output is correct
46	Correct	11 ms	3412 KB	Output is correct
47	Correct	41 ms	4288 KB	Output is correct
48	Correct	11 ms	3120 KB	Output is correct
49	Correct	12 ms	3668 KB	Output is correct
50	Correct	53 ms	4548 KB	Output is correct
51	Correct	12 ms	3488 KB	Output is correct
52	Correct	13 ms	4000 KB	Output is correct
53	Correct	64 ms	5068 KB	Output is correct
54	Correct	15 ms	3668 KB	Output is correct
55	Correct	16 ms	4272 KB	Output is correct
56	Correct	75 ms	5360 KB	Output is correct
57	Correct	17 ms	3924 KB	Output is correct
58	Correct	19 ms	4456 KB	Output is correct
59	Correct	88 ms	5704 KB	Output is correct
60	Correct	18 ms	4108 KB	Output is correct
61	Correct	20 ms	4744 KB	Output is correct
62	Correct	97 ms	6100 KB	Output is correct
63	Correct	80 ms	6080 KB	Output is correct
64	Correct	155 ms	6088 KB	Output is correct
65	Correct	111 ms	6084 KB	Output is correct
66	Correct	109 ms	6088 KB	Output is correct
67	Incorrect	93 ms	5980 KB	Output isn't correct
68	Correct	38 ms	5864 KB	Output is correct
69	Correct	35 ms	6128 KB	Output is correct
70	Correct	34 ms	6100 KB	Output is correct
71	Correct	31 ms	6032 KB	Output is correct
72	Incorrect	24 ms	4172 KB	Output isn't correct
73	Incorrect	26 ms	6484 KB	Output isn't correct
74	Correct	43 ms	6472 KB	Output is correct
75	Correct	52 ms	6484 KB	Output is correct
76	Correct	51 ms	6520 KB	Output is correct
77	Correct	57 ms	6408 KB	Output is correct
78	Incorrect	57 ms	5060 KB	Output isn't correct
79	Correct	38 ms	4808 KB	Output is correct
80	Correct	46 ms	4884 KB	Output is correct
81	Correct	52 ms	4952 KB	Output is correct
82	Correct	46 ms	4880 KB	Output is correct
83	Correct	58 ms	4956 KB	Output is correct
84	Correct	59 ms	4896 KB	Output is correct
85	Correct	58 ms	5084 KB	Output is correct
86	Correct	70 ms	5060 KB	Output is correct
87	Correct	56 ms	5068 KB	Output is correct
88	Correct	59 ms	5140 KB	Output is correct
89	Correct	66 ms	4984 KB	Output is correct
90	Correct	66 ms	5008 KB	Output is correct
91	Correct	75 ms	5152 KB	Output is correct
92	Correct	66 ms	5180 KB	Output is correct