Submission #484095

# Submission time Handle Problem Language Result Execution time Memory
484095 2021-11-02T05:52:16 Z nehasane Mecho (IOI09_mecho) C++14
9 / 100
333 ms 7648 KB
#include <bits/stdc++.h>
using namespace std;
const int MAX_N = 800;
vector <string> field(MAX_N);
bool bees_visited[MAX_N][MAX_N], mecho_visited[MAX_N][MAX_N];
int mecho_dis[MAX_N][MAX_N], bees_dis[MAX_N][MAX_N];
queue <pair <int, int>> mecho_q, bees_q;
int dx[] = {-1, 1, 0, 0};
int dy[] = {0, 0, -1, 1};
int n, s;
bool valid_sq(int x, int y){
    if (x >= 0 && x < n && y >= 0 && y < n && field[x][y] != 'T' && field[x][y] != 'H')
        return true;
    return false;
}
void update_field(queue <pair <int, int>> &q, int max_steps, bool (&visited)[MAX_N][MAX_N], bool (&visited2)[MAX_N][MAX_N], int (&dis)[MAX_N][MAX_N], bool is_mecho){
    while (!q.empty() && dis[q.front().first][q.front().second] != -1){
        int x = q.front().first, y = q.front().second;
        q.pop();
        if (is_mecho && visited2[x][y])
            continue;
        for (int i = 0; i < 4; i++){
            if (valid_sq(x + dx[i], y + dy[i]) && !visited[x+dx[i]][y+dy[i]] && !visited2[x+dx[i]][y+dy[i]]){
                q.push({x+dx[i], y+dy[i]});
                visited[x+dx[i]][y+dy[i]] = true;
                if (dis[x][y] + 1 < max_steps)
                    dis[x+dx[i]][y+dy[i]] = dis[x][y] + 1;
                else
                    dis[x+dx[i]][y+dy[i]] = -1;
            }
        }
    }
}
int main()
{
    // freopen("in.txt", "r", stdin);
    // freopen("out.txt", "w", stdout);
    cin >> n >> s;
    for (int i = 0; i < n; i++)
        cin >> field[i];
    vector <pair <int, int>> hives;
    int startx, starty, home_x, home_y;
    //find Mecho's position
    for (int i = 0; i < n; i++){
        for (int j = 0; j < n; j++){
            if (field[i][j] == 'M'){
                startx = i;
                starty = j;
            }else if (field[i][j] == 'H'){
                hives.push_back({i, j});
            }else if (field[i][j] == 'D'){
                home_x = i;
                home_y = j;
            }
        }
    }
    int l = 0, r = 2*n;
    while (l <= r){
        int eating_time = (l + r) / 2;
        memset(bees_visited, false, sizeof(bees_visited));
        memset(mecho_visited, false, sizeof(mecho_visited));
        memset(bees_dis, 0, sizeof(bees_dis));
        memset(mecho_dis, 0, sizeof(mecho_dis));
        //simulate
        for (auto i : hives){
            bees_q.push({i.first, i.second});
            bees_visited[i.first][i.second] = true;
        }
        if (eating_time > 0){
            for (int i = 0; i < eating_time; i++)
                update_field(bees_q, 1, bees_visited, bees_visited, bees_dis, false);
        }
        mecho_q.push({startx, starty});
        for (int i = eating_time; i <= n*2-2 && !bees_q.empty() && !mecho_q.empty(); i++){
            while (!bees_q.empty() && bees_dis[bees_q.front().first][bees_q.front().second] == -1){
                bees_dis[bees_q.front().first][bees_q.front().second] = 0;
                bees_q.push({bees_q.front().first, bees_q.front().second});
                bees_q.pop();
            }while (!mecho_q.empty() && mecho_dis[mecho_q.front().first][mecho_q.front().second] == -1){
                mecho_dis[mecho_q.front().first][mecho_q.front().second] = 0;
                mecho_q.push({mecho_q.front().first, mecho_q.front().second});
                mecho_q.pop();
            }
            update_field(mecho_q, s, mecho_visited, bees_visited, mecho_dis, true);
            if (mecho_visited[home_x][home_y])
                break;
            update_field(bees_q, 1, bees_visited, bees_visited, bees_dis, false);
        }
        if (mecho_visited[home_x][home_y])
            l = eating_time + 1;
        else
            r = eating_time - 1;
        //empty_queues
        while (!bees_q.empty())
            bees_q.pop();
        while (!mecho_q.empty())
            mecho_q.pop();
    }
    cout << l - 1 << '\n';
}

Compilation message

mecho.cpp: In function 'int main()':
mecho.cpp:89:41: warning: 'home_y' may be used uninitialized in this function [-Wmaybe-uninitialized]
   89 |         if (mecho_visited[home_x][home_y])
      |             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
mecho.cpp:89:41: warning: 'home_x' may be used uninitialized in this function [-Wmaybe-uninitialized]
# Verdict Execution time Memory Grader output
1 Incorrect 3 ms 6476 KB Output isn't correct
2 Incorrect 3 ms 6476 KB Output isn't correct
3 Incorrect 4 ms 6476 KB Output isn't correct
4 Incorrect 3 ms 6476 KB Output isn't correct
5 Correct 3 ms 6476 KB Output is correct
6 Incorrect 4 ms 6476 KB Output isn't correct
7 Incorrect 271 ms 7452 KB Output isn't correct
8 Correct 4 ms 6476 KB Output is correct
9 Incorrect 4 ms 6476 KB Output isn't correct
10 Incorrect 3 ms 6476 KB Output isn't correct
11 Incorrect 3 ms 6476 KB Output isn't correct
12 Incorrect 5 ms 6476 KB Output isn't correct
13 Correct 4 ms 6476 KB Output is correct
14 Correct 4 ms 6476 KB Output is correct
15 Incorrect 4 ms 6476 KB Output isn't correct
16 Incorrect 4 ms 6476 KB Output isn't correct
17 Incorrect 4 ms 6476 KB Output isn't correct
18 Incorrect 4 ms 6536 KB Output isn't correct
19 Incorrect 4 ms 6476 KB Output isn't correct
20 Incorrect 4 ms 6476 KB Output isn't correct
21 Incorrect 6 ms 6580 KB Output isn't correct
22 Incorrect 7 ms 6476 KB Output isn't correct
23 Incorrect 4 ms 6476 KB Output isn't correct
24 Incorrect 5 ms 6476 KB Output isn't correct
25 Incorrect 4 ms 6476 KB Output isn't correct
26 Incorrect 4 ms 6476 KB Output isn't correct
27 Incorrect 4 ms 6476 KB Output isn't correct
28 Incorrect 5 ms 6476 KB Output isn't correct
29 Incorrect 4 ms 6476 KB Output isn't correct
30 Incorrect 4 ms 6476 KB Output isn't correct
31 Incorrect 5 ms 6476 KB Output isn't correct
32 Incorrect 4 ms 6476 KB Output isn't correct
33 Incorrect 7 ms 6732 KB Output isn't correct
34 Incorrect 7 ms 6696 KB Output isn't correct
35 Incorrect 33 ms 6732 KB Output isn't correct
36 Incorrect 8 ms 6656 KB Output isn't correct
37 Incorrect 9 ms 6776 KB Output isn't correct
38 Incorrect 43 ms 6732 KB Output isn't correct
39 Incorrect 12 ms 6732 KB Output isn't correct
40 Incorrect 10 ms 6704 KB Output isn't correct
41 Incorrect 57 ms 6732 KB Output isn't correct
42 Incorrect 10 ms 6988 KB Output isn't correct
43 Incorrect 10 ms 7056 KB Output isn't correct
44 Incorrect 59 ms 7052 KB Output isn't correct
45 Incorrect 11 ms 6996 KB Output isn't correct
46 Incorrect 12 ms 6988 KB Output isn't correct
47 Incorrect 66 ms 7100 KB Output isn't correct
48 Incorrect 12 ms 7116 KB Output isn't correct
49 Incorrect 16 ms 7124 KB Output isn't correct
50 Incorrect 81 ms 7144 KB Output isn't correct
51 Incorrect 14 ms 7212 KB Output isn't correct
52 Incorrect 14 ms 7116 KB Output isn't correct
53 Incorrect 105 ms 7164 KB Output isn't correct
54 Incorrect 15 ms 7244 KB Output isn't correct
55 Incorrect 16 ms 7248 KB Output isn't correct
56 Incorrect 120 ms 7240 KB Output isn't correct
57 Incorrect 18 ms 7196 KB Output isn't correct
58 Incorrect 17 ms 7300 KB Output isn't correct
59 Incorrect 128 ms 7244 KB Output isn't correct
60 Incorrect 19 ms 7316 KB Output isn't correct
61 Incorrect 19 ms 7268 KB Output isn't correct
62 Incorrect 173 ms 7540 KB Output isn't correct
63 Incorrect 204 ms 7236 KB Output isn't correct
64 Incorrect 221 ms 7336 KB Output isn't correct
65 Incorrect 248 ms 7332 KB Output isn't correct
66 Incorrect 289 ms 7336 KB Output isn't correct
67 Correct 211 ms 7336 KB Output is correct
68 Correct 242 ms 7364 KB Output is correct
69 Incorrect 101 ms 7352 KB Output isn't correct
70 Incorrect 333 ms 7244 KB Output isn't correct
71 Incorrect 302 ms 7360 KB Output isn't correct
72 Incorrect 32 ms 7244 KB Output isn't correct
73 Incorrect 310 ms 7540 KB Output isn't correct
74 Incorrect 152 ms 7620 KB Output isn't correct
75 Incorrect 328 ms 7648 KB Output isn't correct
76 Incorrect 300 ms 7632 KB Output isn't correct
77 Incorrect 280 ms 7628 KB Output isn't correct
78 Correct 301 ms 7592 KB Output is correct
79 Incorrect 154 ms 7488 KB Output isn't correct
80 Incorrect 288 ms 7592 KB Output isn't correct
81 Incorrect 263 ms 7500 KB Output isn't correct
82 Incorrect 269 ms 7596 KB Output isn't correct
83 Correct 286 ms 7484 KB Output is correct
84 Incorrect 152 ms 7372 KB Output isn't correct
85 Incorrect 281 ms 7568 KB Output isn't correct
86 Incorrect 276 ms 7560 KB Output isn't correct
87 Incorrect 285 ms 7500 KB Output isn't correct
88 Correct 279 ms 7512 KB Output is correct
89 Incorrect 167 ms 7372 KB Output isn't correct
90 Incorrect 265 ms 7496 KB Output isn't correct
91 Incorrect 242 ms 7616 KB Output isn't correct
92 Incorrect 265 ms 7504 KB Output isn't correct