Submission #777510

#	Time	Username	Problem	Language	Result	Execution time	Memory
777510		OrazB	Tracks in the Snow (BOI13_tracks)	C++17	100 / 100	538 ms	111688 KiB

tracks

#include <iostream>
#include <vector>
#include <queue>
using namespace std;
#define pii pair <int, int>
#define pb push_back
#define ff first
#define ss second
 
int X[] = {-1, 1, 0, 0};
int Y[] = {0, 0, -1, 1};
 
int main ()
{
	ios::sync_with_stdio(false);
	cin.tie(0);
	int n, m;
	cin >> n >> m;
	vector<vector<char>> c(n+1, vector<char>(m+1));
	for (int i = 1; i <= n; i++){
		for (int j = 1; j <= m; j++) cin >> c[i][j];
	}
	int ans = 0;
	vector<vector<int>> dis(n+1, vector<int>(m+1, 0));
	deque<pii> q = {{1, 1}};
	dis[1][1] = 1;	
	while(!q.empty()){
		int x = q.front().ff, y = q.front().ss;
		q.pop_front();
		ans = max(ans, dis[x][y]);
		for (int i = 0; i < 4; i++){
			int a = x+X[i], b = y+Y[i];
			if (a > 0 and b > 0 and a <= n and b <= m and !dis[a][b] and c[a][b] != '.'){
				dis[a][b] = dis[x][y];
				if (c[x][y] != c[a][b]){
					dis[a][b]++;
					q.pb({a, b});
				}else q.push_front({a, b});
			}
		}
	}
	cout << ans << '\n';
}

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