Submission #1205923

#	Time	Username	Problem	Language	Result	Execution time	Memory
1205923		AzeTurk810	Tracks in the Snow (BOI13_tracks)	C++20	68.75 / 100	583 ms	28856 KiB

tracks

/* 
   Tracks_inthe_snow
   Alone again
   Telebe of adicto yani AzeTurk810
*/
#include <bits/stdc++.h>
using namespace std;
using ll = long long;

#define ln '\n'
#define INFi 1e9
#define INFll 1e18
#define MOD int(1e9 + 7)
int n , m;
int dx[] = {1 , -1 , 0 , 0};
int dy[] = {0 , 0 , 1 , -1};

bool is_valid(int x , int y) {
    return (x >= 0 && y >= 0 && x < n && y < n);
}

void solve() {
    cin >> n >> m;
    char c[n][m];
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < m; j++)
        {
            cin >> c[i][j];
        }
        
    }
    queue<pair<int,int>> q[2];
    q[0].push({0 , 0});
    vector<vector<bool>> used(n , vector<bool> (m , false));
    int cur = 0;
    int ans= 0;
    while(!q[cur].empty()) {
        ans++;
        while(!q[cur].empty()) {
            auto tt = q[cur].front();
            q[cur].pop();
            int x = tt.first , y = tt.second;
            // cerr << x << ' ' << y<< ln;
            for (int k = 0; k < 4; k++)
            {
                int cx = x + dx[k] , cy = y + dy[k];
                if(!is_valid(cx , cy) || used[cx][cy] || c[cx][cy] == '.') continue;
                // cerr << cx << ' ' << cy << ' ' << (c[x][y] == c[cx][cy]) << ln;
                if(c[x][y] == c[cx][cy]) {
                    q[cur].push({cx , cy});
                } else {
                    q[cur ^ 1].push({cx , cy});
                }
                used[cx][cy] = true;
            }
        }
        cur ^= 1;
    }
    cout << ans << ln;
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int t = 1;
    // cin >> t; 
    while(t--) solve();
}
//

• Subtask 1: 25 / 30
• Subtask 2: 43.75 / 70