제출 #1272800

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1272800		alexocode	Tracks in the Snow (BOI13_tracks)	C++20	100 / 100	358 ms	118788 KiB

tracks

#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <queue>
#include <map>
#include <utility>
#include <deque>
#include <unordered_map>
using namespace std;
using vi = vector<int>;
typedef long long ll;
typedef unsigned long long ull;
#define pb push_back

const ll MOD = 1e9 + 7;
const ll INF = 1e9;

int dx[4]{1, -1, 0, 0}, dy[4]{0, 0, 1, -1};
int depth[4000][4000];  
string snow[4000];


int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);

  int n, m;
  cin >> n >> m;
  for (int i = 0; i < n; i++) {
    cin >> snow[i];
  }
  deque<pair<int ,int>> q;
  q.push_back({0, 0});
  depth[0][0] = 1;
  int ans = 0;
  while (!q.empty()) {
    auto p = q.front();
    int x = p.first, y = p.second;
    ans = max(ans, depth[x][y]);
    q.pop_front();
    for (int i = 0; i < sizeof(dx) / sizeof(dx[0]); i++) {
      int nx = x + dx[i], ny = y + dy[i];
      if (nx < 0 || nx >= n || ny < 0 || ny >= m || depth[nx][ny] != 0 || snow[nx][ny] == '.') continue;
      if (snow[x][y] == snow[nx][ny]) {
        depth[nx][ny] = depth[x][y];
        q.push_front({nx, ny});
      } else {
        depth[nx][ny] = depth[x][y] + 1;
        q.push_back({nx, ny});
      }
    }
  }
  cout << ans << "\n";
  
  return 0;
}

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