oj.uz

답안 #391414

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
391414 2021-04-18T17:23:53 Z ml1234 Mecho (IOI09_mecho) C++17
84 / 100
 261 ms 6296 KB 
#include <iostream>
#include <string>
#include <queue>
using namespace std;
bool validmecho(int i, int j);
bool validbees(int i, int j);
bool bfs(int starttime);

string grid[800];
int bees[800][800];
int dx[] = {0, -1, 1, 0}, dy[] = {-1, 0, 0, 1};
int n, s;
pair<int, int> mecho;
int main() 
{
    cin >> n >> s;
    for (int i = 0; i < n; i++)
    {
        cin >> grid[i];
        for (int j = 0; j < n; j++)
        {
            if (grid[i][j] == 'M')
            {
                mecho = {i, j};
            }
        }
    }
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < n; j++)
        {
            bees[i][j] = 1e9;
        }
    }
    queue<pair<int, int>> q;
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < n; j++)
        {
            if (grid[i][j] == 'H')
            {
                q.push({i, j});
                bees[i][j] = 0;
            }
        }
    }
    while (!q.empty())
    {
        int curri = q.front().first, currj = q.front().second;
        q.pop();
        for (int d = 0; d < 4; d++)
        {
            int nexti = curri + dx[d], nextj = currj + dy[d];
            if (validbees(nexti, nextj) && bees[nexti][nextj] > bees[curri][currj] + s)
            {
                bees[nexti][nextj] = bees[curri][currj] + s;
                q.push({nexti, nextj});
            }
        }
    }
    int low = 0, high = n * n;
    while (low < high)
    {
        int mid = (low + high + 1) / 2;
        if (bfs(mid))
        {
            low = mid;
        }
        else
        {
            high = mid - 1;
        }
    }
    cout << low << endl;
    return 0;
}

bool ongrid(int i, int j)
{
    return (i >= 0 && i < n && j >= 0 && j < n);
}
bool validbees(int i, int j)
{
    return (ongrid(i, j) && !(grid[i][j] == 'T') && !(grid[i][j] == 'D') && !(grid[i][j] == 'H'));
}
bool validmecho(int i, int j)
{
    return (ongrid(i, j) && !(grid[i][j] == 'T'));
}

bool bfs(int starttime)
{
    if (starttime * s >= bees[mecho.first][mecho.second])
    {
        return false;
    }
    queue<pair<int, int>> q;
    q.push(mecho);
    vector<vector<int>> mechodist(n, vector<int> (n, -1));
    mechodist[mecho.first][mecho.second] = starttime * s;
    while (!q.empty())
    {
        int curri = q.front().first, currj = q.front().second;
        q.pop();
        if (grid[curri][currj] == 'D')
        {
            return true;
        }
        for (int d = 0; d < 4; d++)
        {
            int nexti = curri + dx[d], nextj = currj + dy[d];
            if (!validmecho(nexti, nextj))
            {
                continue;
            }
            if (mechodist[nexti][nextj] == -1)
            {
                if (bees[nexti][nextj] > mechodist[curri][currj] + 1)
                {
                    mechodist[nexti][nextj] = mechodist[curri][currj] + 1;
                    q.push({nexti, nextj});
                }
            }
        }
    }
    return false;
}

Subtask #1
84.0 / 100.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 142 ms 6136 KB Output is correct
8 Incorrect 1 ms 332 KB Output isn't correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 1 ms 332 KB Output is correct
11 Correct 1 ms 332 KB Output is correct
12 Correct 1 ms 460 KB Output is correct
13 Correct 1 ms 460 KB Output is correct
14 Incorrect 1 ms 460 KB Output isn't correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 1 ms 332 KB Output is correct
17 Correct 1 ms 332 KB Output is correct
18 Correct 1 ms 332 KB Output is correct
19 Correct 1 ms 332 KB Output is correct
20 Correct 1 ms 332 KB Output is correct
21 Correct 1 ms 332 KB Output is correct
22 Correct 1 ms 460 KB Output is correct
23 Correct 1 ms 460 KB Output is correct
24 Correct 1 ms 460 KB Output is correct
25 Correct 1 ms 460 KB Output is correct
26 Correct 1 ms 460 KB Output is correct
27 Correct 1 ms 460 KB Output is correct
28 Correct 1 ms 460 KB Output is correct
29 Correct 1 ms 460 KB Output is correct
30 Correct 1 ms 460 KB Output is correct
31 Correct 1 ms 588 KB Output is correct
32 Correct 1 ms 588 KB Output is correct
33 Correct 8 ms 2068 KB Output is correct
34 Correct 9 ms 2080 KB Output is correct
35 Correct 31 ms 2108 KB Output is correct
36 Correct 10 ms 2380 KB Output is correct
37 Correct 11 ms 2380 KB Output is correct
38 Correct 41 ms 2380 KB Output is correct
39 Correct 13 ms 2740 KB Output is correct
40 Correct 13 ms 2748 KB Output is correct
41 Correct 55 ms 2764 KB Output is correct
42 Correct 18 ms 3364 KB Output is correct
43 Correct 17 ms 3360 KB Output is correct
44 Correct 71 ms 3348 KB Output is correct
45 Correct 20 ms 3764 KB Output is correct
46 Correct 20 ms 3796 KB Output is correct
47 Correct 80 ms 3760 KB Output is correct
48 Correct 23 ms 4236 KB Output is correct
49 Correct 22 ms 4224 KB Output is correct
50 Correct 102 ms 4320 KB Output is correct
51 Correct 28 ms 4664 KB Output is correct
52 Correct 27 ms 4680 KB Output is correct
53 Correct 123 ms 4644 KB Output is correct
54 Correct 33 ms 5152 KB Output is correct
55 Correct 30 ms 5144 KB Output is correct
56 Correct 146 ms 5116 KB Output is correct
57 Correct 37 ms 5636 KB Output is correct
58 Correct 36 ms 5636 KB Output is correct
59 Correct 171 ms 5592 KB Output is correct
60 Correct 39 ms 6160 KB Output is correct
61 Correct 46 ms 6296 KB Output is correct
62 Correct 206 ms 6152 KB Output is correct
63 Correct 141 ms 6120 KB Output is correct
64 Correct 261 ms 6240 KB Output is correct
65 Correct 202 ms 6240 KB Output is correct
66 Correct 172 ms 6112 KB Output is correct
67 Incorrect 164 ms 6124 KB Output isn't correct
68 Correct 74 ms 6140 KB Output is correct
69 Correct 70 ms 6164 KB Output is correct
70 Correct 71 ms 6136 KB Output is correct
71 Correct 80 ms 6160 KB Output is correct
72 Correct 48 ms 6144 KB Output is correct
73 Correct 56 ms 6032 KB Output is correct
74 Correct 95 ms 6136 KB Output is correct
75 Correct 120 ms 6204 KB Output is correct
76 Correct 111 ms 6140 KB Output is correct
77 Correct 118 ms 6144 KB Output is correct
78 Incorrect 119 ms 6156 KB Output isn't correct
79 Correct 81 ms 6144 KB Output is correct
80 Correct 104 ms 6140 KB Output is correct
81 Correct 117 ms 6148 KB Output is correct
82 Correct 99 ms 6136 KB Output is correct
83 Correct 129 ms 6156 KB Output is correct
84 Correct 127 ms 6148 KB Output is correct
85 Correct 132 ms 6140 KB Output is correct
86 Correct 135 ms 6152 KB Output is correct
87 Correct 127 ms 6136 KB Output is correct
88 Correct 131 ms 6152 KB Output is correct
89 Correct 149 ms 6148 KB Output is correct
90 Correct 150 ms 6164 KB Output is correct
91 Correct 139 ms 6168 KB Output is correct
92 Correct 133 ms 6140 KB Output is correct