Submission #876681

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
876681	2023-11-22T08:14:54 Z	MisterReaper	Mecho (IOI09_mecho)	C++17	84 / 100	142 ms	7224 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] != 'T') && distBee[_x][_y] == -1) {
				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] != 'T') && 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	5468 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	5448 KB	Output isn't correct
7	Incorrect	78 ms	6492 KB	Output isn't correct
8	Correct	2 ms	5468 KB	Output is correct
9	Correct	1 ms	5360 KB	Output is correct
10	Correct	2 ms	5468 KB	Output is correct
11	Correct	2 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	2 ms	5468 KB	Output is correct
16	Correct	2 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	2 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	5464 KB	Output is correct
25	Correct	2 ms	5468 KB	Output is correct
26	Correct	2 ms	5468 KB	Output is correct
27	Correct	2 ms	5468 KB	Output is correct
28	Correct	2 ms	5468 KB	Output is correct
29	Correct	2 ms	5468 KB	Output is correct
30	Correct	2 ms	5468 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	5724 KB	Output is correct
35	Correct	19 ms	5640 KB	Output is correct
36	Correct	5 ms	5724 KB	Output is correct
37	Correct	6 ms	5720 KB	Output is correct
38	Correct	25 ms	5864 KB	Output is correct
39	Correct	7 ms	5724 KB	Output is correct
40	Correct	7 ms	5724 KB	Output is correct
41	Correct	35 ms	5724 KB	Output is correct
42	Correct	9 ms	5724 KB	Output is correct
43	Correct	8 ms	5720 KB	Output is correct
44	Correct	40 ms	5724 KB	Output is correct
45	Correct	8 ms	5908 KB	Output is correct
46	Correct	10 ms	5724 KB	Output is correct
47	Correct	49 ms	5804 KB	Output is correct
48	Correct	10 ms	5976 KB	Output is correct
49	Correct	11 ms	5976 KB	Output is correct
50	Correct	56 ms	5976 KB	Output is correct
51	Correct	12 ms	5976 KB	Output is correct
52	Correct	12 ms	5980 KB	Output is correct
53	Correct	67 ms	5980 KB	Output is correct
54	Correct	14 ms	5976 KB	Output is correct
55	Correct	14 ms	6080 KB	Output is correct
56	Correct	100 ms	6076 KB	Output is correct
57	Correct	14 ms	5976 KB	Output is correct
58	Correct	16 ms	6120 KB	Output is correct
59	Correct	89 ms	6120 KB	Output is correct
60	Correct	16 ms	5980 KB	Output is correct
61	Correct	17 ms	5988 KB	Output is correct
62	Correct	104 ms	5996 KB	Output is correct
63	Correct	78 ms	5980 KB	Output is correct
64	Correct	142 ms	6148 KB	Output is correct
65	Correct	109 ms	5968 KB	Output is correct
66	Correct	103 ms	5976 KB	Output is correct
67	Correct	89 ms	6224 KB	Output is correct
68	Correct	37 ms	5976 KB	Output is correct
69	Correct	35 ms	5980 KB	Output is correct
70	Correct	27 ms	5980 KB	Output is correct
71	Correct	31 ms	6016 KB	Output is correct
72	Correct	23 ms	5968 KB	Output is correct
73	Correct	34 ms	6800 KB	Output is correct
74	Correct	58 ms	7224 KB	Output is correct
75	Correct	66 ms	6968 KB	Output is correct
76	Correct	67 ms	6972 KB	Output is correct
77	Correct	57 ms	6736 KB	Output is correct
78	Correct	79 ms	6724 KB	Output is correct
79	Correct	47 ms	6744 KB	Output is correct
80	Correct	62 ms	6728 KB	Output is correct
81	Correct	63 ms	6884 KB	Output is correct
82	Correct	57 ms	6744 KB	Output is correct
83	Correct	75 ms	6680 KB	Output is correct
84	Correct	62 ms	6572 KB	Output is correct
85	Correct	70 ms	6744 KB	Output is correct
86	Correct	69 ms	6624 KB	Output is correct
87	Correct	81 ms	6608 KB	Output is correct
88	Correct	74 ms	6492 KB	Output is correct
89	Correct	77 ms	6620 KB	Output is correct
90	Correct	76 ms	6484 KB	Output is correct
91	Correct	74 ms	6488 KB	Output is correct
92	Correct	79 ms	6492 KB	Output is correct