Submission #996994

# Submission time Handle Problem Language Result Execution time Memory
996994 2024-06-11T14:47:12 Z imann Mecho (IOI09_mecho) C++17
50 / 100
135 ms 6532 KB
#include <iostream>
#include <array>
#include <string>
#include <queue>

const int MAX_N = 800 + 1;
const int INF = 1e9;

std::array<std::string, MAX_N> grid;
std::array<std::array<int, MAX_N>, MAX_N> minuteToBeHive, level;

void bfs(int n) {
    std::queue<std::pair<int, int>> q;
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < n; ++j) {
            minuteToBeHive[i][j] = INF;
            if (grid[i][j] == 'H') {
                q.push({i, j});
                minuteToBeHive[i][j] = 0;
            }
        }
    }

    while (!q.empty()) {
        auto v = q.front();
        q.pop();
        if (v.first > 0) {
            if (grid[v.first - 1][v.second] == 'G' || grid[v.first - 1][v.second] == 'M') {
                if (minuteToBeHive[v.first - 1][v.second] == INF)
                    q.push({v.first - 1, v.second});
                minuteToBeHive[v.first - 1][v.second] = std::min(minuteToBeHive[v.first - 1][v.second], minuteToBeHive[v.first][v.second] + 1);
            }
        }
        if (v.first < n - 1) {
            if (grid[v.first + 1][v.second] == 'G' || grid[v.first + 1][v.second] == 'M') {
                if (minuteToBeHive[v.first + 1][v.second] == INF)
                    q.push({v.first + 1, v.second});
                minuteToBeHive[v.first + 1][v.second] = std::min(minuteToBeHive[v.first + 1][v.second], minuteToBeHive[v.first][v.second] + 1);
            }
        }
        if (v.second > 0) {
            if (grid[v.first][v.second - 1] == 'G' || grid[v.first][v.second - 1] == 'M') {
                if (minuteToBeHive[v.first][v.second - 1] == INF)
                    q.push({v.first, v.second - 1});
                minuteToBeHive[v.first][v.second - 1] = std::min(minuteToBeHive[v.first][v.second - 1], minuteToBeHive[v.first][v.second] + 1);
            }
        }
        if (v.second < n - 1) {
            if (grid[v.first][v.second + 1] == 'G' || grid[v.first][v.second + 1] == 'M') {
                if (minuteToBeHive[v.first][v.second + 1] == INF)
                    q.push({v.first, v.second + 1});
                minuteToBeHive[v.first][v.second + 1] = std::min(minuteToBeHive[v.first][v.second + 1], minuteToBeHive[v.first][v.second] + 1);
            }
        }
    }
}

bool bfs2(int n, int s, int startMinute) {
    std::pair<int, int> start, end;
    std::queue<std::pair<int, int>> q;
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < n; ++j) {
            level[i][j] = INF;
            if (grid[i][j] == 'M')
                start = {i, j};
            if (grid[i][j] == 'D')
                end = {i, j};
        }
    }
    q.push(start);
    level[start.first][start.second] = 0;
    if (startMinute + 1. / s > minuteToBeHive[start.first][start.second])
        return false;
    while (!q.empty()) {
        auto v = q.front();
        q.pop();
        if (v.first > 0) {
            if ((grid[v.first - 1][v.second] == 'G' || grid[v.first - 1][v.second] == 'D' || grid[v.first - 1][v.second] == 'M') && (startMinute + (level[v.first][v.second] + 1) / s < minuteToBeHive[v.first - 1][v.second])) {
                if (level[v.first - 1][v.second] == INF)
                    q.push({v.first - 1, v.second});
                level[v.first - 1][v.second] = std::min(level[v.first - 1][v.second], level[v.first][v.second] + 1);
            }
        }
        if (v.first < n - 1) {
            if ((grid[v.first + 1][v.second] == 'G' || grid[v.first + 1][v.second] == 'D' || grid[v.first + 1][v.second] == 'M') && (startMinute + (level[v.first][v.second] + 1) / s < minuteToBeHive[v.first + 1][v.second])) {
                if (level[v.first + 1][v.second] == INF)
                    q.push({v.first + 1, v.second});
                level[v.first + 1][v.second] = std::min(level[v.first + 1][v.second], level[v.first][v.second] + 1);
            }
        }
        if (v.second > 0) {
            if ((grid[v.first][v.second - 1] == 'G' || grid[v.first][v.second - 1] == 'D' || grid[v.first][v.second - 1] == 'M') && (startMinute + (level[v.first][v.second] + 1) / s < minuteToBeHive[v.first][v.second - 1])) {
                if (level[v.first][v.second - 1] == INF)
                    q.push({v.first, v.second - 1});
                level[v.first][v.second - 1] = std::min(level[v.first][v.second - 1], level[v.first][v.second] + 1);
            }
        }
        if (v.second < n - 1) {
            if ((grid[v.first][v.second + 1] == 'G' || grid[v.first][v.second + 1] == 'D' || grid[v.first][v.second + 1] == 'M') && (startMinute + (level[v.first][v.second] + 1) / s < minuteToBeHive[v.first][v.second + 1])) {
                if (level[v.first][v.second + 1] == INF)
                    q.push({v.first, v.second + 1});
                level[v.first][v.second + 1] = std::min(level[v.first][v.second + 1], level[v.first][v.second] + 1);
            }
        }
    }
    return level[end.first][end.second] != INF;
}

int solve(int n, int s) {
    bfs(n);
    int l = 0, r = n;
    while (r - l > 1) {
        int mid = (r + l) / 2;
        if (bfs2(n, s, mid)) {
            l = mid;
        } else {
            r = mid;
        }
    }

    if (bfs2(n, s, l))
        return l;
    return -1;
}

int main() {
    int n, s; std::cin >> n >> s;
    for (int i = 0; i < n; ++i) {
        std::cin >> grid[i];
    }
    std::cout << solve(n, s) << std::endl;
}
# Verdict Execution time Memory Grader output
1 Correct 0 ms 2392 KB Output is correct
2 Correct 0 ms 2396 KB Output is correct
3 Correct 0 ms 2396 KB Output is correct
4 Correct 0 ms 2396 KB Output is correct
5 Correct 0 ms 2396 KB Output is correct
6 Correct 0 ms 2396 KB Output is correct
7 Correct 61 ms 6232 KB Output is correct
8 Correct 1 ms 2392 KB Output is correct
9 Correct 1 ms 2396 KB Output is correct
10 Correct 1 ms 2396 KB Output is correct
11 Correct 1 ms 2396 KB Output is correct
12 Incorrect 1 ms 4700 KB Output isn't correct
13 Correct 1 ms 2440 KB Output is correct
14 Correct 1 ms 4696 KB Output is correct
15 Incorrect 0 ms 2396 KB Output isn't correct
16 Incorrect 0 ms 2396 KB Output isn't correct
17 Incorrect 0 ms 2396 KB Output isn't correct
18 Incorrect 1 ms 2396 KB Output isn't correct
19 Incorrect 0 ms 2396 KB Output isn't correct
20 Incorrect 1 ms 2396 KB Output isn't correct
21 Incorrect 1 ms 2396 KB Output isn't correct
22 Incorrect 1 ms 2396 KB Output isn't correct
23 Incorrect 1 ms 2652 KB Output isn't correct
24 Incorrect 1 ms 2652 KB Output isn't correct
25 Incorrect 1 ms 4700 KB Output isn't correct
26 Incorrect 1 ms 4700 KB Output isn't correct
27 Incorrect 1 ms 4700 KB Output isn't correct
28 Incorrect 1 ms 4700 KB Output isn't correct
29 Incorrect 1 ms 4700 KB Output isn't correct
30 Incorrect 1 ms 4700 KB Output isn't correct
31 Incorrect 1 ms 4700 KB Output isn't correct
32 Incorrect 1 ms 4700 KB Output isn't correct
33 Incorrect 11 ms 4916 KB Output isn't correct
34 Incorrect 14 ms 4920 KB Output isn't correct
35 Correct 16 ms 4920 KB Output is correct
36 Incorrect 12 ms 4940 KB Output isn't correct
37 Incorrect 14 ms 4696 KB Output isn't correct
38 Correct 21 ms 4700 KB Output is correct
39 Incorrect 17 ms 4968 KB Output isn't correct
40 Incorrect 17 ms 4956 KB Output isn't correct
41 Correct 26 ms 4952 KB Output is correct
42 Incorrect 19 ms 5224 KB Output isn't correct
43 Incorrect 22 ms 5220 KB Output isn't correct
44 Correct 33 ms 5212 KB Output is correct
45 Incorrect 24 ms 5212 KB Output isn't correct
46 Incorrect 28 ms 5208 KB Output isn't correct
47 Correct 39 ms 5212 KB Output is correct
48 Incorrect 29 ms 5264 KB Output isn't correct
49 Incorrect 33 ms 5208 KB Output isn't correct
50 Correct 50 ms 5264 KB Output is correct
51 Incorrect 33 ms 5468 KB Output isn't correct
52 Incorrect 40 ms 5464 KB Output isn't correct
53 Correct 58 ms 5468 KB Output is correct
54 Incorrect 39 ms 5724 KB Output isn't correct
55 Incorrect 45 ms 5720 KB Output isn't correct
56 Correct 69 ms 5720 KB Output is correct
57 Incorrect 50 ms 5980 KB Output isn't correct
58 Incorrect 51 ms 5868 KB Output isn't correct
59 Correct 81 ms 5976 KB Output is correct
60 Incorrect 50 ms 6232 KB Output isn't correct
61 Incorrect 58 ms 6232 KB Output isn't correct
62 Correct 94 ms 6232 KB Output is correct
63 Correct 71 ms 6072 KB Output is correct
64 Incorrect 135 ms 6232 KB Output isn't correct
65 Correct 124 ms 6480 KB Output is correct
66 Correct 91 ms 6236 KB Output is correct
67 Correct 80 ms 6072 KB Output is correct
68 Correct 36 ms 6232 KB Output is correct
69 Correct 34 ms 6236 KB Output is correct
70 Correct 39 ms 6228 KB Output is correct
71 Correct 31 ms 6232 KB Output is correct
72 Correct 27 ms 6236 KB Output is correct
73 Correct 31 ms 6492 KB Output is correct
74 Correct 43 ms 6532 KB Output is correct
75 Correct 50 ms 6492 KB Output is correct
76 Correct 47 ms 6484 KB Output is correct
77 Correct 51 ms 6504 KB Output is correct
78 Correct 55 ms 6492 KB Output is correct
79 Correct 52 ms 6488 KB Output is correct
80 Correct 48 ms 6492 KB Output is correct
81 Correct 55 ms 6492 KB Output is correct
82 Correct 62 ms 6492 KB Output is correct
83 Correct 58 ms 6232 KB Output is correct
84 Correct 58 ms 6444 KB Output is correct
85 Correct 58 ms 6288 KB Output is correct
86 Correct 61 ms 6232 KB Output is correct
87 Correct 68 ms 6436 KB Output is correct
88 Correct 68 ms 6220 KB Output is correct
89 Correct 69 ms 6484 KB Output is correct
90 Correct 68 ms 6232 KB Output is correct
91 Correct 65 ms 6164 KB Output is correct
92 Correct 67 ms 6236 KB Output is correct