Submission #978629

# Submission time Handle Problem Language Result Execution time Memory
978629 2024-05-09T11:57:37 Z Bodisha Mecho (IOI09_mecho) C++17
81 / 100
1000 ms 7504 KB
#include <bits/stdc++.h>
#define MAX_N 801

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]) {
        return true;
    }
    if(home_pos.first - 1 >= 0 && visited[home_pos.first - 1][home_pos.second]) {
        return true;
    }
    if(home_pos.second + 1 < n && visited[home_pos.first][home_pos.second + 1]) {
        return true;
    }
    if(home_pos.second - 1 >= 0 && visited[home_pos.first][home_pos.second - 1]) {
        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];
            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 2392 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 1 ms 2392 KB Output is correct
4 Correct 1 ms 2396 KB Output is correct
5 Correct 1 ms 2484 KB Output is correct
6 Correct 0 ms 2396 KB Output is correct
7 Correct 982 ms 7428 KB Output is correct
8 Correct 1 ms 2396 KB Output is correct
9 Correct 1 ms 2408 KB Output is correct
10 Correct 0 ms 2396 KB Output is correct
11 Correct 1 ms 2396 KB Output is correct
12 Correct 1 ms 4696 KB Output is correct
13 Correct 1 ms 2652 KB Output is correct
14 Correct 1 ms 4700 KB Output is correct
15 Correct 1 ms 2648 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 2648 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 2652 KB Output is correct
22 Correct 1 ms 2652 KB Output is correct
23 Correct 1 ms 2652 KB Output is correct
24 Correct 1 ms 2652 KB Output is correct
25 Correct 1 ms 4700 KB Output is correct
26 Correct 1 ms 4700 KB Output is correct
27 Correct 1 ms 5108 KB Output is correct
28 Correct 1 ms 4700 KB Output is correct
29 Correct 1 ms 4696 KB Output is correct
30 Correct 1 ms 4700 KB Output is correct
31 Correct 1 ms 4700 KB Output is correct
32 Correct 2 ms 4700 KB Output is correct
33 Correct 5 ms 5208 KB Output is correct
34 Correct 5 ms 5208 KB Output is correct
35 Correct 296 ms 5460 KB Output is correct
36 Correct 7 ms 5212 KB Output is correct
37 Correct 6 ms 5212 KB Output is correct
38 Correct 277 ms 5604 KB Output is correct
39 Correct 10 ms 5464 KB Output is correct
40 Correct 7 ms 5464 KB Output is correct
41 Correct 301 ms 5640 KB Output is correct
42 Correct 12 ms 5724 KB Output is correct
43 Correct 8 ms 5464 KB Output is correct
44 Correct 391 ms 5652 KB Output is correct
45 Correct 12 ms 5468 KB Output is correct
46 Correct 9 ms 5468 KB Output is correct
47 Correct 449 ms 5920 KB Output is correct
48 Correct 14 ms 5720 KB Output is correct
49 Correct 11 ms 5724 KB Output is correct
50 Correct 517 ms 6096 KB Output is correct
51 Correct 16 ms 5976 KB Output is correct
52 Correct 13 ms 5976 KB Output is correct
53 Correct 475 ms 6472 KB Output is correct
54 Correct 19 ms 6236 KB Output is correct
55 Correct 15 ms 6300 KB Output is correct
56 Correct 468 ms 6632 KB Output is correct
57 Correct 23 ms 6740 KB Output is correct
58 Correct 17 ms 6492 KB Output is correct
59 Correct 382 ms 6816 KB Output is correct
60 Correct 25 ms 6752 KB Output is correct
61 Correct 21 ms 6748 KB Output is correct
62 Incorrect 236 ms 7180 KB Output isn't correct
63 Incorrect 92 ms 6748 KB Output isn't correct
64 Incorrect 116 ms 6756 KB Output isn't correct
65 Incorrect 108 ms 6752 KB Output isn't correct
66 Incorrect 93 ms 6744 KB Output isn't correct
67 Correct 115 ms 6748 KB Output is correct
68 Incorrect 43 ms 6748 KB Output isn't correct
69 Incorrect 45 ms 6772 KB Output isn't correct
70 Incorrect 46 ms 6748 KB Output isn't correct
71 Incorrect 37 ms 6748 KB Output isn't correct
72 Correct 34 ms 6744 KB Output is correct
73 Correct 284 ms 7320 KB Output is correct
74 Execution timed out 1076 ms 7440 KB Time limit exceeded
75 Execution timed out 1063 ms 7232 KB Time limit exceeded
76 Execution timed out 1044 ms 7352 KB Time limit exceeded
77 Execution timed out 1027 ms 7212 KB Time limit exceeded
78 Execution timed out 1074 ms 7268 KB Time limit exceeded
79 Execution timed out 1008 ms 7220 KB Time limit exceeded
80 Execution timed out 1004 ms 7252 KB Time limit exceeded
81 Execution timed out 1036 ms 7432 KB Time limit exceeded
82 Execution timed out 1056 ms 7444 KB Time limit exceeded
83 Correct 667 ms 7316 KB Output is correct
84 Correct 632 ms 7060 KB Output is correct
85 Correct 627 ms 7072 KB Output is correct
86 Correct 704 ms 7076 KB Output is correct
87 Correct 674 ms 7504 KB Output is correct
88 Correct 820 ms 7136 KB Output is correct
89 Correct 754 ms 7252 KB Output is correct
90 Correct 805 ms 7360 KB Output is correct
91 Correct 792 ms 7384 KB Output is correct
92 Correct 905 ms 7176 KB Output is correct