Submission #978642

# Submission time Handle Problem Language Result Execution time Memory
978642 2024-05-09T12:16:14 Z Bodisha Mecho (IOI09_mecho) C++17
77 / 100
1000 ms 7612 KB
#include <bits/stdc++.h>
#define MAX_N 800

using namespace std;

int n, s;
char grid[MAX_N][MAX_N];
bool visited[MAX_N][MAX_N];
int beed[MAX_N][MAX_N];
int steps[MAX_N][MAX_N];

bool check(int t) {
    pair<int, int> mecho_pos, home_pos;
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < n; j++) {
            visited[i][j] = false;
            if(grid[i][j] == 'M') {
                mecho_pos = {i, j};
            }
            if(grid[i][j] == 'D') {
                home_pos = {i, j};
            }
        }
    }
    if(t >= beed[mecho_pos.first][mecho_pos.second]) {
        return false;
    }
    queue<pair<pair<int, int>, int>> newq;
    visited[mecho_pos.first][mecho_pos.second] = true;
    newq.push({mecho_pos, 0});
    while(!newq.empty()) {
        pair<pair<int, int>, int> curr = newq.front(); 
        newq.pop();
        int tmp = t + ((curr.second + 1) / s);
        if(curr.first.first + 1 < n && tmp < beed[curr.first.first + 1][curr.first.second] && !visited[curr.first.first + 1][curr.first.second] && (grid[curr.first.first + 1][curr.first.second] == 'G' || grid[curr.first.first + 1][curr.first.second] == 'M')) {
            visited[curr.first.first + 1][curr.first.second] = true;
            newq.push({{curr.first.first + 1, curr.first.second}, curr.second + 1});
        }
        if(curr.first.first - 1 >= 0 && tmp < beed[curr.first.first - 1][curr.first.second] && !visited[curr.first.first - 1][curr.second] && (grid[curr.first.first - 1][curr.first.second] == 'G' || grid[curr.first.first - 1][curr.first.second] == 'M')) {
            visited[curr.first.first - 1][curr.first.second] = true;
            newq.push({{curr.first.first - 1, curr.first.second}, curr.second + 1});
        }
        if(curr.first.second + 1 < n && tmp < beed[curr.first.first][curr.first.second + 1] && !visited[curr.first.first][curr.first.second + 1] && (grid[curr.first.first][curr.first.second + 1] == 'G' || grid[curr.first.first][curr.first.second + 1] == 'M')) {
            visited[curr.first.first][curr.first.second + 1] = true;
            newq.push({{curr.first.first, curr.first.second + 1}, curr.second + 1});
        }
        if(curr.first.second - 1 >= 0 && tmp < beed[curr.first.first][curr.first.second - 1] && !visited[curr.first.first][curr.first.second - 1] && (grid[curr.first.first][curr.first.second - 1] == 'G' || grid[curr.first.first][curr.first.second - 1] == 'M')) {
            visited[curr.first.first][curr.first.second - 1] = true;
            newq.push({{curr.first.first, curr.first.second - 1}, curr.second + 1});
        }
    }
    if(home_pos.first + 1 < n && visited[home_pos.first + 1][home_pos.second] && (grid[home_pos.first + 1][home_pos.second] == 'M' || grid[home_pos.first + 1][home_pos.second] == 'G')) {
        return true;
    }
    if(home_pos.first - 1 >= 0 && visited[home_pos.first - 1][home_pos.second] && (grid[home_pos.first - 1][home_pos.second] == 'M' || grid[home_pos.first - 1][home_pos.second] == 'G')) {
        return true;
    }
    if(home_pos.second + 1 < n && visited[home_pos.first][home_pos.second + 1] && (grid[home_pos.first][home_pos.second + 1] == 'M' || grid[home_pos.first][home_pos.second + 1] == 'G')) {
        return true;
    }
    if(home_pos.second - 1 >= 0 && visited[home_pos.first][home_pos.second - 1] && (grid[home_pos.first][home_pos.second - 1] == 'M' || grid[home_pos.first][home_pos.second - 1] == 'G')) {
        return true;
    }
    return false;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    vector<pair<int, int>> hives;
    pair<int, int> mecho_pos;
    cin >> n >> s;
    for(int i = 0; i < n; i++) {
        string tmp;
        cin >> tmp;
        for(int j = 0; j < n; j++) {
            grid[i][j] = tmp[j];
            beed[i][j] = INT_MAX - n * n;
            if(grid[i][j] == 'H') {
                hives.push_back({i, j});
            }
            if(grid[i][j] == 'M') {
                mecho_pos = {i, j};
            }
        }
    }
    queue<pair<int, int>> q;
    visited[mecho_pos.first][mecho_pos.second] = true;
    steps[mecho_pos.first][mecho_pos.second] = 0;
    q.push(mecho_pos);
    while(!q.empty()) {
        pair<int, int> curr = q.front(); 
        q.pop();
        if(curr.first + 1 < n && !visited[curr.first + 1][curr.second] && (grid[curr.first + 1][curr.second] == 'G' || grid[curr.first + 1][curr.second] == 'M')) {
            visited[curr.first + 1][curr.second] = true;
            steps[curr.first + 1][curr.second] = steps[curr.first][curr.second] + 1;
            q.push({curr.first + 1, curr.second});
        }
        if(curr.first - 1 >= 0 && !visited[curr.first - 1][curr.second] && (grid[curr.first - 1][curr.second] == 'G' || grid[curr.first - 1][curr.second] == 'M')) {
            visited[curr.first - 1][curr.second] = true;
            steps[curr.first - 1][curr.second] = steps[curr.first][curr.second] + 1;
            q.push({curr.first - 1, curr.second});
        }
        if(curr.second + 1 < n && !visited[curr.first][curr.second + 1] && (grid[curr.first][curr.second + 1] == 'G' || grid[curr.first][curr.second + 1] == 'M')) {
            visited[curr.first][curr.second + 1] = true;
            steps[curr.first][curr.second + 1] = steps[curr.first][curr.second] + 1;
            q.push({curr.first, curr.second + 1});
        }
        if(curr.second - 1 >= 0 && !visited[curr.first][curr.second - 1] && (grid[curr.first][curr.second - 1] == 'G' || grid[curr.first][curr.second - 1] == 'M')) {
            visited[curr.first][curr.second - 1] = true;
            steps[curr.first][curr.second - 1] = steps[curr.first][curr.second] + 1;
            q.push({curr.first, curr.second - 1});
        }
    }
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < n; j++) {
            visited[i][j] = false;
        }
    }
    for(auto iter : hives) {
        visited[iter.first][iter.second] = true;
        beed[iter.first][iter.second] = 0;
        q.push(iter);
    }
    while(!q.empty()) {
        pair<int, int> curr = q.front(); 
        q.pop();
        if(curr.first + 1 < n && !visited[curr.first + 1][curr.second] && (grid[curr.first + 1][curr.second] == 'G' || grid[curr.first + 1][curr.second] == 'M')) {
            visited[curr.first + 1][curr.second] = true;
            beed[curr.first + 1][curr.second] = beed[curr.first][curr.second] + 1;
            q.push({curr.first + 1, curr.second});
        }
        if(curr.first - 1 >= 0 && !visited[curr.first - 1][curr.second] && (grid[curr.first - 1][curr.second] == 'G' || grid[curr.first - 1][curr.second] == 'M')) {
            visited[curr.first - 1][curr.second] = true;
            beed[curr.first - 1][curr.second] = beed[curr.first][curr.second] + 1;
            q.push({curr.first - 1, curr.second});
        }
        if(curr.second + 1 < n && !visited[curr.first][curr.second + 1] && (grid[curr.first][curr.second + 1] == 'G' || grid[curr.first][curr.second + 1] == 'M')) {
            visited[curr.first][curr.second + 1] = true;
            beed[curr.first][curr.second + 1] = beed[curr.first][curr.second] + 1;
            q.push({curr.first, curr.second + 1});
        }
        if(curr.second - 1 >= 0 && !visited[curr.first][curr.second - 1] && (grid[curr.first][curr.second - 1] == 'G' || grid[curr.first][curr.second - 1] == 'M')) {
            visited[curr.first][curr.second - 1] = true;
            beed[curr.first][curr.second - 1] = beed[curr.first][curr.second] + 1;
            q.push({curr.first, curr.second - 1});
        }
    }
    int l = 0, r = n * n;
    int ans = -1;
    // true true true ... (true) false false
    while(l <= r) {
        int mid = l + (r - l) / 2;
        if(check(mid)) {
            ans = mid;
            l = mid + 1;
        } else {
            r = mid - 1;
        }
    }
    cout << ans;
    return 0;
}
# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 0 ms 2396 KB Output is correct
3 Correct 1 ms 2396 KB Output is correct
4 Correct 0 ms 2396 KB Output is correct
5 Correct 1 ms 2396 KB Output is correct
6 Correct 1 ms 2548 KB Output is correct
7 Execution timed out 1063 ms 7212 KB Time limit exceeded
8 Correct 1 ms 2392 KB Output is correct
9 Correct 1 ms 2392 KB Output is correct
10 Correct 1 ms 2396 KB Output is correct
11 Correct 1 ms 2396 KB Output is correct
12 Correct 2 ms 4700 KB Output is correct
13 Correct 1 ms 2652 KB Output is correct
14 Correct 2 ms 4700 KB Output is correct
15 Correct 1 ms 2396 KB Output is correct
16 Correct 1 ms 2396 KB Output is correct
17 Correct 1 ms 2396 KB Output is correct
18 Correct 1 ms 2396 KB Output is correct
19 Correct 1 ms 2652 KB Output is correct
20 Correct 1 ms 2652 KB Output is correct
21 Correct 1 ms 2648 KB Output is correct
22 Correct 2 ms 2652 KB Output is correct
23 Correct 1 ms 2648 KB Output is correct
24 Correct 1 ms 2648 KB Output is correct
25 Correct 1 ms 4700 KB Output is correct
26 Correct 1 ms 4700 KB Output is correct
27 Correct 2 ms 4700 KB Output is correct
28 Correct 1 ms 4700 KB Output is correct
29 Correct 1 ms 4700 KB Output is correct
30 Correct 1 ms 4700 KB Output is correct
31 Correct 1 ms 4696 KB Output is correct
32 Correct 1 ms 4700 KB Output is correct
33 Correct 6 ms 5212 KB Output is correct
34 Correct 5 ms 5212 KB Output is correct
35 Correct 331 ms 5528 KB Output is correct
36 Correct 7 ms 5384 KB Output is correct
37 Correct 8 ms 5212 KB Output is correct
38 Correct 374 ms 5532 KB Output is correct
39 Correct 9 ms 5464 KB Output is correct
40 Correct 7 ms 5212 KB Output is correct
41 Correct 349 ms 5628 KB Output is correct
42 Correct 11 ms 5468 KB Output is correct
43 Correct 9 ms 5468 KB Output is correct
44 Correct 453 ms 5660 KB Output is correct
45 Correct 13 ms 5464 KB Output is correct
46 Correct 10 ms 5604 KB Output is correct
47 Correct 518 ms 5888 KB Output is correct
48 Correct 17 ms 5732 KB Output is correct
49 Correct 12 ms 5724 KB Output is correct
50 Correct 567 ms 6252 KB Output is correct
51 Correct 20 ms 5980 KB Output is correct
52 Correct 14 ms 6060 KB Output is correct
53 Correct 558 ms 6320 KB Output is correct
54 Correct 27 ms 6232 KB Output is correct
55 Correct 23 ms 6232 KB Output is correct
56 Correct 517 ms 6576 KB Output is correct
57 Correct 24 ms 6492 KB Output is correct
58 Correct 18 ms 6492 KB Output is correct
59 Correct 467 ms 6992 KB Output is correct
60 Correct 27 ms 6748 KB Output is correct
61 Correct 23 ms 6488 KB Output is correct
62 Incorrect 274 ms 6948 KB Output isn't correct
63 Incorrect 61 ms 6748 KB Output isn't correct
64 Incorrect 63 ms 6744 KB Output isn't correct
65 Incorrect 55 ms 6752 KB Output isn't correct
66 Incorrect 68 ms 6748 KB Output isn't correct
67 Correct 55 ms 6752 KB Output is correct
68 Incorrect 41 ms 6744 KB Output isn't correct
69 Incorrect 45 ms 6748 KB Output isn't correct
70 Incorrect 45 ms 6748 KB Output isn't correct
71 Incorrect 48 ms 6776 KB Output isn't correct
72 Correct 37 ms 6744 KB Output is correct
73 Correct 338 ms 7280 KB Output is correct
74 Execution timed out 1031 ms 7252 KB Time limit exceeded
75 Execution timed out 1014 ms 7612 KB Time limit exceeded
76 Execution timed out 1040 ms 7284 KB Time limit exceeded
77 Execution timed out 1049 ms 7220 KB Time limit exceeded
78 Execution timed out 1032 ms 7264 KB Time limit exceeded
79 Execution timed out 1074 ms 7204 KB Time limit exceeded
80 Execution timed out 1033 ms 7336 KB Time limit exceeded
81 Execution timed out 1044 ms 7248 KB Time limit exceeded
82 Execution timed out 1020 ms 7216 KB Time limit exceeded
83 Correct 845 ms 7320 KB Output is correct
84 Correct 739 ms 7048 KB Output is correct
85 Correct 692 ms 7060 KB Output is correct
86 Correct 772 ms 7296 KB Output is correct
87 Correct 846 ms 7236 KB Output is correct
88 Correct 883 ms 7124 KB Output is correct
89 Correct 849 ms 7068 KB Output is correct
90 Correct 907 ms 7116 KB Output is correct
91 Correct 872 ms 7244 KB Output is correct
92 Correct 979 ms 7312 KB Output is correct