Submission #484076

# Submission time Handle Problem Language Result Execution time Memory
484076 2021-11-02T05:20:38 Z nehasane Mecho (IOI09_mecho) C++14
28 / 100
226 ms 8000 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 && visited[x][y] && 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)
            update_field(bees_q, eating_time, 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 << r << '\n';
}

Compilation message

mecho.cpp: In function 'int main()':
mecho.cpp:87:41: warning: 'home_y' may be used uninitialized in this function [-Wmaybe-uninitialized]
   87 |         if (mecho_visited[home_x][home_y])
      |             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
mecho.cpp:87:41: warning: 'home_x' may be used uninitialized in this function [-Wmaybe-uninitialized]
# Verdict Execution time Memory Grader output
1 Correct 3 ms 6476 KB Output is correct
2 Incorrect 4 ms 6476 KB Output isn't correct
3 Correct 3 ms 6476 KB Output is correct
4 Incorrect 3 ms 6476 KB Output isn't correct
5 Correct 4 ms 6532 KB Output is correct
6 Incorrect 3 ms 6476 KB Output isn't correct
7 Incorrect 173 ms 7656 KB Output isn't correct
8 Correct 4 ms 6476 KB Output is correct
9 Correct 4 ms 6476 KB Output is correct
10 Correct 4 ms 6476 KB Output is correct
11 Correct 4 ms 6476 KB Output is correct
12 Incorrect 4 ms 6476 KB Output isn't correct
13 Incorrect 4 ms 6476 KB Output isn't correct
14 Correct 5 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 6476 KB Output isn't correct
19 Incorrect 4 ms 6584 KB Output isn't correct
20 Incorrect 5 ms 6476 KB Output isn't correct
21 Incorrect 4 ms 6476 KB Output isn't correct
22 Incorrect 4 ms 6476 KB Output isn't correct
23 Incorrect 4 ms 6476 KB Output isn't correct
24 Incorrect 4 ms 6588 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 5 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 6508 KB Output isn't correct
32 Incorrect 5 ms 6604 KB Output isn't correct
33 Incorrect 8 ms 6868 KB Output isn't correct
34 Incorrect 8 ms 6860 KB Output isn't correct
35 Correct 24 ms 6860 KB Output is correct
36 Incorrect 8 ms 6860 KB Output isn't correct
37 Incorrect 9 ms 6860 KB Output isn't correct
38 Correct 33 ms 6860 KB Output is correct
39 Incorrect 9 ms 7000 KB Output isn't correct
40 Incorrect 10 ms 7000 KB Output isn't correct
41 Correct 39 ms 6988 KB Output is correct
42 Incorrect 10 ms 7244 KB Output isn't correct
43 Incorrect 11 ms 7244 KB Output isn't correct
44 Correct 50 ms 7304 KB Output is correct
45 Incorrect 12 ms 7260 KB Output isn't correct
46 Incorrect 14 ms 7332 KB Output isn't correct
47 Correct 61 ms 7244 KB Output is correct
48 Incorrect 13 ms 7372 KB Output isn't correct
49 Incorrect 13 ms 7408 KB Output isn't correct
50 Correct 68 ms 7400 KB Output is correct
51 Incorrect 14 ms 7368 KB Output isn't correct
52 Incorrect 15 ms 7372 KB Output isn't correct
53 Correct 79 ms 7400 KB Output is correct
54 Incorrect 15 ms 7512 KB Output isn't correct
55 Incorrect 16 ms 7460 KB Output isn't correct
56 Correct 98 ms 7616 KB Output is correct
57 Incorrect 18 ms 7488 KB Output isn't correct
58 Incorrect 20 ms 7432 KB Output isn't correct
59 Correct 103 ms 7500 KB Output is correct
60 Incorrect 19 ms 7492 KB Output isn't correct
61 Incorrect 20 ms 7492 KB Output isn't correct
62 Correct 125 ms 7500 KB Output is correct
63 Incorrect 173 ms 7592 KB Output isn't correct
64 Correct 150 ms 7500 KB Output is correct
65 Correct 180 ms 7536 KB Output is correct
66 Correct 191 ms 7500 KB Output is correct
67 Correct 189 ms 7712 KB Output is correct
68 Correct 174 ms 7616 KB Output is correct
69 Correct 127 ms 7620 KB Output is correct
70 Correct 167 ms 7620 KB Output is correct
71 Correct 185 ms 7628 KB Output is correct
72 Incorrect 207 ms 7520 KB Output isn't correct
73 Incorrect 125 ms 7840 KB Output isn't correct
74 Correct 184 ms 7880 KB Output is correct
75 Correct 193 ms 8000 KB Output is correct
76 Correct 226 ms 7872 KB Output is correct
77 Correct 181 ms 7876 KB Output is correct
78 Correct 208 ms 7848 KB Output is correct
79 Correct 186 ms 7852 KB Output is correct
80 Correct 184 ms 7752 KB Output is correct
81 Correct 210 ms 7756 KB Output is correct
82 Correct 192 ms 7844 KB Output is correct
83 Correct 214 ms 7756 KB Output is correct
84 Correct 187 ms 7756 KB Output is correct
85 Correct 208 ms 7876 KB Output is correct
86 Correct 197 ms 7704 KB Output is correct
87 Correct 188 ms 7808 KB Output is correct
88 Correct 215 ms 7764 KB Output is correct
89 Correct 182 ms 7756 KB Output is correct
90 Correct 191 ms 7752 KB Output is correct
91 Correct 187 ms 7664 KB Output is correct
92 Correct 181 ms 7756 KB Output is correct