Submission #379167

#	Time	Username	Problem	Language	Result	Execution time	Memory
379167		ruadhan	Tracks in the Snow (BOI13_tracks)	C++14	0 / 100	2133 ms	584876 KiB

tracks

#include <bits/stdc++.h>
#define pi pair<int, int>
using namespace std;
const int MAXN = 505;

char grid[MAXN][MAXN];
int dist[MAXN][MAXN];
queue<pi> q;
int n, m, ans = 0;

int main()
{
    cin >> n >> m;
    for (int i = 0; i < n; i++)
        for (int j = 0; j < m; j++)
            cin >> grid[i][j];

    // for (int i = 0; i < n; i++)
    // {
    //     for (int j = 0; j < m; j++)
    //         cout << grid[i][j];
    //     cout << endl;
    // }
    // cout << endl;

    dist[0][0] = 1;
    q.push({0, 0});
    while (!q.empty())
    {
        // for (int i = 0; i < n; i++)
        // {
        //     for (int j = 0; j < m; j++)
        //         cout << dist[i][j] << " ";
        //     cout << endl;
        // }
        // cout << endl;
        int i = q.front().first, j = q.front().second;
        q.pop();
        ans = max(ans, dist[i][j]);
        if (i + 1 < n)
        {
            if (grid[i + 1][j] == '.')
            {
            }
            else if (grid[i][j] == grid[i + 1][j])
            {
                dist[i + 1][j] = min((dist[i + 1][j] == 0 ? INT_MAX : dist[i + 1][j]), dist[i][j]);
                q.push({i + 1, j});
            }
            else if (grid[i][j] != grid[i + 1][j])
            {
                dist[i + 1][j] = min((dist[i + 1][j] == 0 ? INT_MAX : dist[i + 1][j]), dist[i][j] + 1);
                q.push({i + 1, j});
            }
        }
        if (j + 1 < m)
        {
            if (grid[i][j + 1] == '.')
            {
            }
            else if (grid[i][j] == grid[i][j + 1])
            {
                dist[i][j + 1] = min((dist[i][j + 1] == 0 ? INT_MAX : dist[i][j + 1]), dist[i][j]);
                q.push({i, j + 1});
            }
            else if (grid[i][j] != grid[i][j + 1])
            {
                dist[i][j + 1] = min((dist[i][j + 1] == 0 ? INT_MAX : dist[i][j + 1]), dist[i][j] + 1);
                q.push({i, j + 1});
            }
        }
    }
    cout << ans << endl;
    return 0;
}

• Subtask 1: 0 / 30
• Subtask 2: 0 / 70