Submission #816005

# Submission time Handle Problem Language Result Execution time Memory
816005 2023-08-09T03:39:55 Z powervic08 Mecho (IOI09_mecho) C++17
100 / 100
161 ms 6524 KB
#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) {
	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();
		minHiveDist[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] != 'T' && grid[r][c] != 'D') {
				visited[r][c] = true;
				q.push({ {r, c}, dist + S });
			}
		}
	}
}
 
void bfs2(int startR, int startC, int wait) {
	visited.clear(); visited.resize(N, vector<bool>(N));
	if (minHiveDist[startR][startC] <= wait * S) return;
	queue<pair<pii, int>> q; q.push({ {startR, startC}, wait * S });
	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] != 'T') {
				if (dist + 1 < minHiveDist[r][c]) {
					visited[r][c] = true;
					q.push({ {r, c}, dist + 1 });
				}
			}
		}
	}
}
bool works(int wait) {
	bfs2(mR, mC, wait);
	return visited[dR][dC];
}
 
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[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 << (works(low) ? low : low - 1) << endl;
}
# 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 67 ms 5036 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 0 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 468 KB Output is correct
13 Correct 1 ms 604 KB Output is correct
14 Correct 1 ms 596 KB Output is correct
15 Correct 0 ms 340 KB Output is correct
16 Correct 0 ms 340 KB Output is correct
17 Correct 1 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 1 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 7 ms 2260 KB Output is correct
35 Correct 22 ms 2852 KB Output is correct
36 Correct 8 ms 2260 KB Output is correct
37 Correct 6 ms 2516 KB Output is correct
38 Correct 23 ms 3204 KB Output is correct
39 Correct 6 ms 2516 KB Output is correct
40 Correct 8 ms 2772 KB Output is correct
41 Correct 31 ms 3540 KB Output is correct
42 Correct 8 ms 2700 KB Output is correct
43 Correct 9 ms 3028 KB Output is correct
44 Correct 39 ms 3796 KB Output is correct
45 Correct 10 ms 2992 KB Output is correct
46 Correct 10 ms 3412 KB Output is correct
47 Correct 44 ms 4180 KB Output is correct
48 Correct 11 ms 3156 KB Output is correct
49 Correct 11 ms 3588 KB Output is correct
50 Correct 58 ms 4564 KB Output is correct
51 Correct 12 ms 3412 KB Output is correct
52 Correct 13 ms 3924 KB Output is correct
53 Correct 78 ms 4948 KB Output is correct
54 Correct 15 ms 3620 KB Output is correct
55 Correct 16 ms 4224 KB Output is correct
56 Correct 78 ms 5360 KB Output is correct
57 Correct 16 ms 3872 KB Output is correct
58 Correct 18 ms 4544 KB Output is correct
59 Correct 87 ms 5692 KB Output is correct
60 Correct 18 ms 4140 KB Output is correct
61 Correct 20 ms 4772 KB Output is correct
62 Correct 107 ms 6088 KB Output is correct
63 Correct 96 ms 6084 KB Output is correct
64 Correct 161 ms 5988 KB Output is correct
65 Correct 122 ms 6088 KB Output is correct
66 Correct 103 ms 6084 KB Output is correct
67 Correct 101 ms 6036 KB Output is correct
68 Correct 44 ms 6044 KB Output is correct
69 Correct 37 ms 6100 KB Output is correct
70 Correct 46 ms 6060 KB Output is correct
71 Correct 33 ms 6072 KB Output is correct
72 Correct 25 ms 4156 KB Output is correct
73 Correct 34 ms 6524 KB Output is correct
74 Correct 45 ms 6468 KB Output is correct
75 Correct 55 ms 6476 KB Output is correct
76 Correct 67 ms 6524 KB Output is correct
77 Correct 56 ms 6484 KB Output is correct
78 Correct 62 ms 5188 KB Output is correct
79 Correct 40 ms 4824 KB Output is correct
80 Correct 48 ms 4812 KB Output is correct
81 Correct 55 ms 4972 KB Output is correct
82 Correct 48 ms 4900 KB Output is correct
83 Correct 62 ms 5020 KB Output is correct
84 Correct 65 ms 4896 KB Output is correct
85 Correct 61 ms 5032 KB Output is correct
86 Correct 81 ms 5068 KB Output is correct
87 Correct 70 ms 4972 KB Output is correct
88 Correct 63 ms 5168 KB Output is correct
89 Correct 71 ms 4964 KB Output is correct
90 Correct 73 ms 5088 KB Output is correct
91 Correct 71 ms 5280 KB Output is correct
92 Correct 64 ms 5148 KB Output is correct