oj.uz

Submission #1015789

# Submission time Handle Problem Language Result Execution time Memory
1015789 2024-07-06T19:18:07 Z KALARRY Tracks in the Snow (BOI13_tracks) C++14
100 / 100
 806 ms 120964 KB 
//chockolateman

#include<bits/stdc++.h>

using namespace std;

const int INF = 1e9;

int H,W,di[4] = {1,-1,0,0},dj[4] = {0,0,1,-1},dist[4005][4005];
char grid[4005][4005];

bool is_ok(int i,int j)
{
    if(i >= 1 && i <= H && j >= 1 && j <= W && grid[i][j] != '.')
        return true;
    return false;
}

void BFS(int starti,int startj)
{
    for(int i = 1 ; i <= H ; i++)
        for(int j = 1 ; j <= W ; j++)
            if(grid[i][j]!='.')
                dist[i][j] = INF;
    deque<pair<int,int>> q;
    dist[starti][startj] = 1;
    q.push_back({starti,startj});
    while(!q.empty())
    {
        pair<int,int> v = q.front();
        int i = v.first;
        int j = v.second;
        q.pop_front();
        for(int k = 0 ; k <= 3 ; k++)
        {
            int new_i = i + di[k];
            int new_j = j + dj[k];
            if(is_ok(new_i,new_j))
            {
                if(grid[i][j]==grid[new_i][new_j])
                {
                    if(dist[i][j] < dist[new_i][new_j])
                    {
                        dist[new_i][new_j] = dist[i][j];
                        q.push_front({new_i,new_j});
                    }
                }
                else
                {
                    if(dist[i][j] + 1 < dist[new_i][new_j])
                    {
                        dist[new_i][new_j] = dist[i][j] + 1;
                        q.push_back({new_i,new_j});
                    }
                }
            }
        }
    }
}

int main()
{
    scanf("%d%d",&H,&W);
    for(int i = 1 ; i <= H ; i++)
        for(int j = 1 ; j <= W ; j++)
            scanf(" %c",&grid[i][j]);
    BFS(1,1);
    int ans = 0;
    for(int i = 1 ; i <= H ; i++)
        for(int j = 1 ; j <= W ; j++)
            ans = max(ans,dist[i][j]);
    printf("%d\n",ans);
    return 0;
}

Compilation message

tracks.cpp: In function 'int main()':
tracks.cpp:63:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   63 |     scanf("%d%d",&H,&W);
      |     ~~~~~^~~~~~~~~~~~~~
tracks.cpp:66:18: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   66 |             scanf(" %c",&grid[i][j]);
      |             ~~~~~^~~~~~~~~~~~~~~~~~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 12892 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 1 ms 4700 KB Output is correct
4 Correct 9 ms 12892 KB Output is correct
5 Correct 4 ms 8792 KB Output is correct
6 Correct 0 ms 2396 KB Output is correct
7 Correct 1 ms 4700 KB Output is correct
8 Correct 1 ms 6748 KB Output is correct
9 Correct 1 ms 6748 KB Output is correct
10 Correct 4 ms 8796 KB Output is correct
11 Correct 3 ms 8792 KB Output is correct
12 Correct 7 ms 8792 KB Output is correct
13 Correct 6 ms 8644 KB Output is correct
14 Correct 4 ms 8792 KB Output is correct
15 Correct 15 ms 12904 KB Output is correct
16 Correct 16 ms 12996 KB Output is correct
17 Correct 16 ms 12892 KB Output is correct
18 Correct 10 ms 12888 KB Output is correct

Subtask #2
70.0 / 70.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 32092 KB Output is correct
2 Correct 71 ms 21444 KB Output is correct
3 Correct 541 ms 57680 KB Output is correct
4 Correct 144 ms 32600 KB Output is correct
5 Correct 336 ms 47448 KB Output is correct
6 Correct 800 ms 108000 KB Output is correct
7 Correct 10 ms 32092 KB Output is correct
8 Correct 8 ms 32312 KB Output is correct
9 Correct 3 ms 2396 KB Output is correct
10 Correct 1 ms 2396 KB Output is correct
11 Correct 7 ms 31564 KB Output is correct
12 Correct 2 ms 6744 KB Output is correct
13 Correct 65 ms 20064 KB Output is correct
14 Correct 51 ms 18260 KB Output is correct
15 Correct 33 ms 18264 KB Output is correct
16 Correct 27 ms 10856 KB Output is correct
17 Correct 163 ms 27988 KB Output is correct
18 Correct 144 ms 34128 KB Output is correct
19 Correct 142 ms 32104 KB Output is correct
20 Correct 116 ms 26196 KB Output is correct
21 Correct 405 ms 43616 KB Output is correct
22 Correct 345 ms 44628 KB Output is correct
23 Correct 371 ms 38308 KB Output is correct
24 Correct 332 ms 40804 KB Output is correct
25 Correct 591 ms 78692 KB Output is correct
26 Correct 471 ms 120672 KB Output is correct
27 Correct 738 ms 120964 KB Output is correct
28 Correct 786 ms 107996 KB Output is correct
29 Correct 806 ms 106184 KB Output is correct
30 Correct 757 ms 110292 KB Output is correct
31 Correct 613 ms 63572 KB Output is correct
32 Correct 626 ms 109576 KB Output is correct