Submission #484156

# Submission time Handle Problem Language Result Execution time Memory
484156 2021-11-02T08:28:42 Z nehasane Mecho (IOI09_mecho) C++14
14 / 100
519 ms 10180 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], eating_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, bool is_mecho){
    if (x >= 0 && x < n && y >= 0 && y < n){
        if (is_mecho && (field[x][y] == 'G' || field[x][y] == 'D' || field[x][y] == 'M'))
            return true;
        else if (!is_mecho && (field[x][y] == 'G' || field[x][y] == 'M'))
            return true;
        return false;
    }
    return false;
}
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 = n*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));
        //move bees
        for (auto i : hives){
            bees_q.push({i.first, i.second});
            bees_visited[i.first][i.second] = true;
        }
        while (!bees_q.empty()){
            int x = bees_q.front().first, y = bees_q.front().second;
            bees_q.pop();
            for (int i = 0; i < 4; i++){
                int nx = x + dx[i], ny = y + dy[i];
                if (valid_sq(nx, ny, false) && !bees_visited[nx][ny]){
                    if (eating_dis[x][y] < eating_time){
                        eating_dis[nx][ny] = eating_dis[x][y] + 1;
                    }else{
                        bees_dis[nx][ny] = bees_dis[x][y] + 1;
                        eating_dis[nx][ny] = INT_MAX;
                    }
                    bees_q.push({nx, ny});
                    bees_visited[nx][ny] = true;
                }
            }
        }
        mecho_q.push({startx, starty});
        mecho_visited[startx][starty] = true;
        if (bees_visited[startx][starty] && eating_time > 0)
            mecho_q.pop();
        while (!mecho_q.empty()){
            int x = mecho_q.front().first, y = mecho_q.front().second;
            mecho_q.pop();
            for (int i = 0; i < 4; i++){
                int nx = x + dx[i], ny = y + dy[i];
                if (valid_sq(nx, ny, true) && !mecho_visited[nx][ny] && (mecho_dis[x][y] + 1) / s < bees_dis[nx][ny]){
                    mecho_visited[nx][ny] = true;
                    mecho_q.push({nx, ny});
                    mecho_dis[nx][ny] = mecho_dis[x][y] + 1;
                }
            }
        }
        bool mecho_reached = false;
        for (int i = 0; i < 4; i++){
            int nx = home_x+ dx[i], ny = home_y + dy[i];
            if (valid_sq(nx, ny, true)){
                if (bees_dis[nx][ny] > (mecho_dis[nx][ny] / s) && mecho_visited[nx][ny]){
                    mecho_reached = true;
                    break;
                }
            }
        }
        if (mecho_reached)
            l = eating_time + 1;
        else
            r = eating_time - 1;
        }
    cout << l - 1 << '\n';
}

Compilation message

mecho.cpp: In function 'int main()':
mecho.cpp:75:40: warning: 'starty' may be used uninitialized in this function [-Wmaybe-uninitialized]
   75 |         if (bees_visited[startx][starty] && eating_time > 0)
      |             ~~~~~~~~~~~~~~~~~~~~~~~~~~~^
mecho.cpp:75:40: warning: 'startx' may be used uninitialized in this function [-Wmaybe-uninitialized]
mecho.cpp:91:37: warning: 'home_y' may be used uninitialized in this function [-Wmaybe-uninitialized]
   91 |             int nx = home_x+ dx[i], ny = home_y + dy[i];
      |                                     ^~
mecho.cpp:91:17: warning: 'home_x' may be used uninitialized in this function [-Wmaybe-uninitialized]
   91 |             int nx = home_x+ dx[i], ny = home_y + dy[i];
      |                 ^~
# Verdict Execution time Memory Grader output
1 Incorrect 3 ms 6476 KB Output isn't correct
2 Incorrect 4 ms 6600 KB Output isn't correct
3 Incorrect 3 ms 6476 KB Output isn't correct
4 Incorrect 4 ms 6604 KB Output isn't correct
5 Correct 4 ms 6604 KB Output is correct
6 Incorrect 4 ms 6604 KB Output isn't correct
7 Incorrect 454 ms 9952 KB Output isn't correct
8 Correct 4 ms 6604 KB Output is correct
9 Incorrect 5 ms 6604 KB Output isn't correct
10 Incorrect 5 ms 6604 KB Output isn't correct
11 Incorrect 4 ms 6604 KB Output isn't correct
12 Correct 6 ms 6732 KB Output is correct
13 Correct 5 ms 6732 KB Output is correct
14 Correct 9 ms 6776 KB Output is correct
15 Incorrect 5 ms 6604 KB Output isn't correct
16 Incorrect 5 ms 6604 KB Output isn't correct
17 Incorrect 5 ms 6668 KB Output isn't correct
18 Incorrect 5 ms 6604 KB Output isn't correct
19 Incorrect 7 ms 6604 KB Output isn't correct
20 Incorrect 7 ms 6676 KB Output isn't correct
21 Incorrect 6 ms 6708 KB Output isn't correct
22 Incorrect 5 ms 6604 KB Output isn't correct
23 Incorrect 5 ms 6732 KB Output isn't correct
24 Incorrect 5 ms 6732 KB Output isn't correct
25 Incorrect 6 ms 6780 KB Output isn't correct
26 Incorrect 6 ms 6776 KB Output isn't correct
27 Incorrect 7 ms 6800 KB Output isn't correct
28 Incorrect 6 ms 6732 KB Output isn't correct
29 Incorrect 7 ms 6808 KB Output isn't correct
30 Incorrect 7 ms 6732 KB Output isn't correct
31 Incorrect 7 ms 6732 KB Output isn't correct
32 Incorrect 7 ms 6732 KB Output isn't correct
33 Incorrect 59 ms 7832 KB Output isn't correct
34 Incorrect 42 ms 7756 KB Output isn't correct
35 Incorrect 58 ms 7756 KB Output isn't correct
36 Incorrect 50 ms 8012 KB Output isn't correct
37 Incorrect 55 ms 8024 KB Output isn't correct
38 Incorrect 78 ms 8028 KB Output isn't correct
39 Incorrect 68 ms 8184 KB Output isn't correct
40 Incorrect 64 ms 8192 KB Output isn't correct
41 Incorrect 107 ms 8140 KB Output isn't correct
42 Incorrect 83 ms 8524 KB Output isn't correct
43 Incorrect 83 ms 8544 KB Output isn't correct
44 Incorrect 119 ms 8524 KB Output isn't correct
45 Incorrect 91 ms 8780 KB Output isn't correct
46 Incorrect 134 ms 8808 KB Output isn't correct
47 Incorrect 162 ms 8812 KB Output isn't correct
48 Incorrect 114 ms 9108 KB Output isn't correct
49 Incorrect 110 ms 9036 KB Output isn't correct
50 Incorrect 173 ms 9036 KB Output isn't correct
51 Incorrect 130 ms 9164 KB Output isn't correct
52 Incorrect 133 ms 9236 KB Output isn't correct
53 Incorrect 220 ms 9308 KB Output isn't correct
54 Incorrect 149 ms 9420 KB Output isn't correct
55 Incorrect 145 ms 9424 KB Output isn't correct
56 Incorrect 295 ms 9540 KB Output isn't correct
57 Incorrect 190 ms 9624 KB Output isn't correct
58 Incorrect 186 ms 9636 KB Output isn't correct
59 Incorrect 312 ms 9640 KB Output isn't correct
60 Incorrect 207 ms 9828 KB Output isn't correct
61 Incorrect 197 ms 9784 KB Output isn't correct
62 Incorrect 313 ms 9836 KB Output isn't correct
63 Correct 445 ms 9844 KB Output is correct
64 Incorrect 436 ms 9924 KB Output isn't correct
65 Incorrect 428 ms 9796 KB Output isn't correct
66 Incorrect 501 ms 9856 KB Output isn't correct
67 Correct 417 ms 9796 KB Output is correct
68 Correct 519 ms 9868 KB Output is correct
69 Incorrect 505 ms 9868 KB Output isn't correct
70 Incorrect 480 ms 9872 KB Output isn't correct
71 Incorrect 490 ms 9872 KB Output isn't correct
72 Incorrect 490 ms 9876 KB Output isn't correct
73 Incorrect 459 ms 10144 KB Output isn't correct
74 Incorrect 464 ms 10136 KB Output isn't correct
75 Incorrect 445 ms 10140 KB Output isn't correct
76 Incorrect 479 ms 10144 KB Output isn't correct
77 Incorrect 464 ms 10140 KB Output isn't correct
78 Correct 455 ms 10180 KB Output is correct
79 Incorrect 470 ms 10104 KB Output isn't correct
80 Incorrect 474 ms 10108 KB Output isn't correct
81 Incorrect 464 ms 10100 KB Output isn't correct
82 Incorrect 476 ms 10084 KB Output isn't correct
83 Correct 465 ms 10064 KB Output is correct
84 Incorrect 476 ms 10052 KB Output isn't correct
85 Incorrect 469 ms 10180 KB Output isn't correct
86 Incorrect 463 ms 10040 KB Output isn't correct
87 Incorrect 459 ms 10064 KB Output isn't correct
88 Correct 489 ms 10008 KB Output is correct
89 Incorrect 476 ms 10044 KB Output isn't correct
90 Incorrect 463 ms 10048 KB Output isn't correct
91 Incorrect 470 ms 10004 KB Output isn't correct
92 Incorrect 468 ms 9924 KB Output isn't correct