Submission #1012614

# Submission time Handle Problem Language Result Execution time Memory
1012614 2024-07-02T12:06:29 Z toast12 Mecho (IOI09_mecho) C++14
73 / 100
140 ms 6320 KB
#include <bits/stdc++.h>
using namespace std;
 
const int MAXN = 800;
 
int n, s;
vector<vector<char>> grid;
vector<vector<int>> dist;
 
int honey;
 
bool reachable(int mecho, int bee) {
    return ((mecho-honey)/s < bee-honey) && (mecho != -1) && (bee != -1); 
}
 
void bfs(queue<pair<int, int>> &q, vector<vector<int>> &d) {
    while (!q.empty()) {
        int x = q.front().first;
        int y = q.front().second;
        q.pop();
        if (x < 1 || y < 1 || x > n || y > n)
            continue;
        if (d[x+1][y] == -1 && grid[x+1][y] != 'X' && reachable(d[x][y]+1, dist[x+1][y])) {
            q.push({x+1, y});
            d[x+1][y] = d[x][y]+1;
        }
        if (d[x-1][y] == -1 && grid[x-1][y] != 'X' && reachable(d[x][y]+1, dist[x-1][y])) {
            q.push({x-1, y});
            d[x-1][y] = d[x][y]+1;
        }
        if (d[x][y+1] == -1 && grid[x][y+1] != 'X' && reachable(d[x][y]+1, dist[x][y+1])) {
            q.push({x, y+1});
            d[x][y+1] = d[x][y]+1;
        }
        if (d[x][y-1] == -1 && grid[x][y-1] != 'X' && reachable(d[x][y]+1, dist[x][y-1])) {
            q.push({x, y-1});
            d[x][y-1] = d[x][y]+1;
        }
    }
}
 
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cin >> n >> s;
    grid.resize(n+2, vector<char>(n+2, '.'));
    pair<int, int> start, end;
    queue<pair<int, int>> q;
    dist.resize(n+2, vector<int>(n+2, -1));
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= n; j++) {
            cin >> grid[i][j];
            if (grid[i][j] == 'G')
                grid[i][j] = '.';
            else if (grid[i][j] == 'T')
                grid[i][j] = 'X';
            else if (grid[i][j] == 'M')
                start = {i, j};
            else if (grid[i][j] == 'D')
                end = {i, j};
            else {
                q.push({i, j});
                dist[i][j] = 0;
            }
        }
    }
    // distance for bees
    while (!q.empty()) {
        int x = q.front().first;
        int y = q.front().second;
        q.pop();
        if (x < 1 || y < 1 || x > n || y > n)
            continue;
        if (dist[x+1][y] == -1 && grid[x+1][y] != 'X') {
            q.push({x+1, y});
            dist[x+1][y] = dist[x][y]+1;
        }
        if (dist[x-1][y] == -1 && grid[x-1][y] != 'X') {
            q.push({x-1, y});
            dist[x-1][y] = dist[x][y]+1;
        }
        if (dist[x][y+1] == -1 && grid[x][y+1] != 'X') {
            q.push({x, y+1});
            dist[x][y+1] = dist[x][y]+1;
        }
        if (dist[x][y-1] == -1 && grid[x][y-1] != 'X') {
            q.push({x, y-1});
            dist[x][y-1] = dist[x][y]+1;
        }
    }
    int lo = 0, hi = MAXN*MAXN;
    int ans = -1;
    while (lo <= hi) {
        int mid = (lo+hi)/2;
        vector<vector<int>> d(n+2, vector<int>(n+2, -1));
        d[start.first][start.second] = mid;
        honey = mid;
        q.push(start);
        bfs(q, d);
        int temp = dist[end.first][end.second];
        bool poss = reachable(d[end.first-1][end.second], temp);
        poss |= reachable(d[end.first+1][end.second], temp);
        poss |= reachable(d[end.first][end.second-1], temp);
        poss |= reachable(d[end.first][end.second+1], temp);
        if (poss) {
            lo = mid+1;
            ans = mid;
        }
        else {
            hi = mid-1;
        }
    }
    cout << ans << '\n';
    return 0;
}
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Incorrect 0 ms 348 KB Output isn't correct
3 Correct 0 ms 348 KB Output is correct
4 Incorrect 0 ms 348 KB Output isn't correct
5 Correct 0 ms 348 KB Output is correct
6 Incorrect 0 ms 348 KB Output isn't correct
7 Incorrect 52 ms 6268 KB Output isn't correct
8 Correct 0 ms 344 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 0 ms 348 KB Output is correct
12 Incorrect 1 ms 348 KB Output isn't correct
13 Incorrect 0 ms 348 KB Output isn't correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 348 KB Output is correct
16 Correct 0 ms 348 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 452 KB Output is correct
20 Correct 0 ms 348 KB Output is correct
21 Correct 0 ms 344 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Correct 0 ms 344 KB Output is correct
24 Correct 0 ms 348 KB Output is correct
25 Correct 0 ms 348 KB Output is correct
26 Correct 0 ms 348 KB Output is correct
27 Correct 0 ms 348 KB Output is correct
28 Correct 0 ms 348 KB Output is correct
29 Correct 0 ms 348 KB Output is correct
30 Correct 0 ms 348 KB Output is correct
31 Correct 0 ms 348 KB Output is correct
32 Correct 0 ms 348 KB Output is correct
33 Correct 5 ms 1568 KB Output is correct
34 Correct 5 ms 1584 KB Output is correct
35 Correct 12 ms 1588 KB Output is correct
36 Correct 7 ms 1884 KB Output is correct
37 Correct 7 ms 1884 KB Output is correct
38 Correct 17 ms 1792 KB Output is correct
39 Correct 8 ms 2300 KB Output is correct
40 Correct 7 ms 2300 KB Output is correct
41 Correct 21 ms 2368 KB Output is correct
42 Correct 10 ms 2768 KB Output is correct
43 Correct 10 ms 2756 KB Output is correct
44 Correct 28 ms 2720 KB Output is correct
45 Correct 12 ms 3224 KB Output is correct
46 Correct 13 ms 3272 KB Output is correct
47 Correct 32 ms 3252 KB Output is correct
48 Correct 14 ms 3712 KB Output is correct
49 Correct 14 ms 3924 KB Output is correct
50 Correct 39 ms 3708 KB Output is correct
51 Correct 15 ms 4340 KB Output is correct
52 Correct 15 ms 4316 KB Output is correct
53 Correct 41 ms 4324 KB Output is correct
54 Correct 19 ms 5176 KB Output is correct
55 Correct 19 ms 4924 KB Output is correct
56 Correct 56 ms 4892 KB Output is correct
57 Correct 22 ms 5592 KB Output is correct
58 Correct 22 ms 5596 KB Output is correct
59 Correct 65 ms 5556 KB Output is correct
60 Correct 27 ms 6320 KB Output is correct
61 Correct 26 ms 6256 KB Output is correct
62 Correct 70 ms 6236 KB Output is correct
63 Correct 78 ms 6212 KB Output is correct
64 Correct 140 ms 6208 KB Output is correct
65 Correct 103 ms 6184 KB Output is correct
66 Correct 86 ms 6232 KB Output is correct
67 Correct 87 ms 6208 KB Output is correct
68 Correct 45 ms 6244 KB Output is correct
69 Correct 45 ms 6260 KB Output is correct
70 Correct 40 ms 6224 KB Output is correct
71 Correct 42 ms 6316 KB Output is correct
72 Incorrect 35 ms 6252 KB Output isn't correct
73 Incorrect 34 ms 6232 KB Output isn't correct
74 Correct 40 ms 6316 KB Output is correct
75 Correct 49 ms 6244 KB Output is correct
76 Correct 41 ms 6248 KB Output is correct
77 Correct 43 ms 6236 KB Output is correct
78 Correct 47 ms 6232 KB Output is correct
79 Correct 36 ms 6268 KB Output is correct
80 Correct 40 ms 6276 KB Output is correct
81 Correct 46 ms 6276 KB Output is correct
82 Correct 48 ms 6308 KB Output is correct
83 Correct 52 ms 6260 KB Output is correct
84 Correct 46 ms 6272 KB Output is correct
85 Correct 52 ms 6264 KB Output is correct
86 Correct 47 ms 6244 KB Output is correct
87 Correct 49 ms 6248 KB Output is correct
88 Correct 52 ms 6232 KB Output is correct
89 Correct 51 ms 6236 KB Output is correct
90 Correct 65 ms 6232 KB Output is correct
91 Correct 50 ms 6280 KB Output is correct
92 Correct 57 ms 6252 KB Output is correct