Submission #876679

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
876679	2023-11-22T08:11:53 Z	MisterReaper	Mecho (IOI09_mecho)	C++17	84 / 100	147 ms	7768 KB

mecho

#include <bits/stdc++.h>
using namespace std;
using i64 = long long;

const int MAXN = 800 + 5;

char matrix[MAXN][MAXN];
int distBee[MAXN][MAXN];
int distBear[MAXN][MAXN];

int dx[4] = {0, 1, 0, -1};
int dy[4] = {1, 0, -1, 0};

#define ONLINE_JUDGE
void solve() {
	memset(distBee, -1, sizeof(distBee));

	int n, s;
	cin >> n >> s;

	pair <int, int> initial;
	pair <int, int> home;

	queue <array <int, 3>> q;
	for(int i = 1; i <= n; i++) {
		for(int j = 1; j <= n; j++) {
			cin >> matrix[i][j];
			if(matrix[i][j] == 'H') {
				q.push({0, i, j});
			} else if(matrix[i][j] == 'M') {
				initial = {i, j};
			} else if(matrix[i][j] == 'D') {
				home = {i, j};
			}
		}
	}

	auto in = [&](int x, int y) -> bool {
		return 1 <= min(x, y) && max(x, y) <= n;
	};

	while(!q.empty()) {
		auto [d, x, y] = q.front();
		q.pop();
		if(distBee[x][y] != -1) {
			continue;
		}

		distBee[x][y] = d;
		for(int dir = 0; dir < 4; dir++) {
			int _x = x + dx[dir], _y = y + dy[dir];
			if(in(_x, _y) && (matrix[_x][_y] == 'D' || matrix[_x][_y] == 'G' || matrix[_x][_y] == 'M')) {
				q.push({d +1, _x, _y});
			}
		}
	}

	auto check = [&](int k) -> bool {
		memset(distBear, -1, sizeof(distBear));

		q.push({s * k, initial.first, initial.second});
		while(!q.empty()) {
			auto [d, x, y] = q.front();
			q.pop();
			if(distBear[x][y] != -1 || (distBee[x][y] != -1 && d >= distBee[x][y] * s)) {
				continue;
			}

			//cerr << d << " :: " << x << " " << y << " | " << distBee[x][y] << "\n";
			distBear[x][y] = d;
			for(int dir = 0; dir < 4; dir++) {
				int _x = x + dx[dir], _y = y + dy[dir];
				if(in(_x, _y) && (matrix[_x][_y] == 'G' || matrix[_x][_y] == 'D') && distBear[_x][_y] == -1) {
					q.push({d +1, _x, _y});
				}
			}
		}

		if(distBear[home.first][home.second] == -1) {
			return false;
		}

		return true;
	};
	
	int l = 0, r = n * n + 2, ans = -1;
	while(l <= r) {
		int mid = (l + r) / 2;
		if(check(mid)) {
			ans = mid;
			l = mid +1;
		} else {
			r = mid -1;
		}
	}

	cout << ans;

	return;
}

signed main() {
	#ifndef ONLINE_JUDGE
		freopen(".in", "r", stdin);
		freopen(".out", "w", stdout);
	#endif

	ios_base::sync_with_stdio(false);
	cin.tie(NULL); cout.tie(NULL);

	int t = 1; //cin >> t;
	for(int i = 1; i <= t; i++) {
		solve();
	}

	return 0;
}

Subtask #1

84.0 / 100.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	5468 KB	Output is correct
2	Incorrect	1 ms	5320 KB	Output isn't correct
3	Correct	1 ms	5468 KB	Output is correct
4	Incorrect	1 ms	5468 KB	Output isn't correct
5	Correct	1 ms	5468 KB	Output is correct
6	Incorrect	1 ms	5468 KB	Output isn't correct
7	Incorrect	91 ms	6640 KB	Output isn't correct
8	Correct	1 ms	5464 KB	Output is correct
9	Correct	1 ms	5468 KB	Output is correct
10	Correct	1 ms	5468 KB	Output is correct
11	Correct	1 ms	5468 KB	Output is correct
12	Incorrect	2 ms	5468 KB	Output isn't correct
13	Correct	2 ms	5468 KB	Output is correct
14	Correct	2 ms	5468 KB	Output is correct
15	Correct	1 ms	5468 KB	Output is correct
16	Correct	1 ms	5468 KB	Output is correct
17	Correct	2 ms	5468 KB	Output is correct
18	Correct	2 ms	5468 KB	Output is correct
19	Correct	2 ms	5468 KB	Output is correct
20	Correct	2 ms	5468 KB	Output is correct
21	Correct	1 ms	5468 KB	Output is correct
22	Correct	2 ms	5468 KB	Output is correct
23	Correct	2 ms	5468 KB	Output is correct
24	Correct	2 ms	5468 KB	Output is correct
25	Correct	2 ms	5468 KB	Output is correct
26	Correct	2 ms	5464 KB	Output is correct
27	Correct	2 ms	5468 KB	Output is correct
28	Correct	2 ms	5720 KB	Output is correct
29	Correct	2 ms	5468 KB	Output is correct
30	Correct	2 ms	5720 KB	Output is correct
31	Correct	2 ms	5468 KB	Output is correct
32	Correct	2 ms	5468 KB	Output is correct
33	Correct	5 ms	5724 KB	Output is correct
34	Correct	5 ms	5804 KB	Output is correct
35	Correct	21 ms	5976 KB	Output is correct
36	Correct	6 ms	5848 KB	Output is correct
37	Correct	6 ms	5724 KB	Output is correct
38	Correct	27 ms	5868 KB	Output is correct
39	Correct	7 ms	5720 KB	Output is correct
40	Correct	7 ms	5888 KB	Output is correct
41	Correct	35 ms	5724 KB	Output is correct
42	Correct	8 ms	5736 KB	Output is correct
43	Correct	9 ms	5724 KB	Output is correct
44	Correct	42 ms	5724 KB	Output is correct
45	Correct	9 ms	5936 KB	Output is correct
46	Correct	11 ms	5968 KB	Output is correct
47	Correct	57 ms	5972 KB	Output is correct
48	Correct	11 ms	5976 KB	Output is correct
49	Correct	12 ms	5980 KB	Output is correct
50	Correct	63 ms	5860 KB	Output is correct
51	Correct	12 ms	5976 KB	Output is correct
52	Correct	14 ms	5976 KB	Output is correct
53	Correct	74 ms	5980 KB	Output is correct
54	Correct	14 ms	5976 KB	Output is correct
55	Correct	15 ms	5900 KB	Output is correct
56	Correct	84 ms	6092 KB	Output is correct
57	Correct	16 ms	5976 KB	Output is correct
58	Correct	19 ms	5980 KB	Output is correct
59	Correct	95 ms	5980 KB	Output is correct
60	Correct	17 ms	5980 KB	Output is correct
61	Correct	20 ms	5980 KB	Output is correct
62	Correct	116 ms	6180 KB	Output is correct
63	Correct	80 ms	6144 KB	Output is correct
64	Correct	147 ms	5968 KB	Output is correct
65	Correct	112 ms	5980 KB	Output is correct
66	Correct	91 ms	5984 KB	Output is correct
67	Correct	88 ms	6144 KB	Output is correct
68	Correct	40 ms	6224 KB	Output is correct
69	Correct	40 ms	6224 KB	Output is correct
70	Correct	32 ms	6060 KB	Output is correct
71	Correct	36 ms	6228 KB	Output is correct
72	Correct	28 ms	6224 KB	Output is correct
73	Correct	41 ms	7568 KB	Output is correct
74	Correct	65 ms	7748 KB	Output is correct
75	Correct	76 ms	7768 KB	Output is correct
76	Correct	64 ms	7764 KB	Output is correct
77	Correct	67 ms	7764 KB	Output is correct
78	Correct	87 ms	7628 KB	Output is correct
79	Correct	56 ms	7504 KB	Output is correct
80	Correct	64 ms	7460 KB	Output is correct
81	Correct	78 ms	7440 KB	Output is correct
82	Correct	71 ms	7452 KB	Output is correct
83	Correct	85 ms	7136 KB	Output is correct
84	Correct	73 ms	7228 KB	Output is correct
85	Correct	76 ms	7248 KB	Output is correct
86	Correct	77 ms	7368 KB	Output is correct
87	Correct	86 ms	7248 KB	Output is correct
88	Correct	92 ms	6824 KB	Output is correct
89	Correct	86 ms	6928 KB	Output is correct
90	Correct	88 ms	7000 KB	Output is correct
91	Correct	89 ms	6900 KB	Output is correct
92	Correct	91 ms	7068 KB	Output is correct