16234.cpp

// Authored by : yongjunleeme
// Co-authored by : -
// http://boj.kr/7f59ea777614493ba11da2e4a572f9d9
#include <bits/stdc++.h>
using namespace std;
#define X first
#define Y second

int n, l, r;
int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};
int board[105][105];
int vis[105][105];
int ans = 0;

int main(void){
  ios::sync_with_stdio(0);
  cin.tie(0);
  cin >> n >> l >> r;

  for(int i = 0; i < n; i++)
    for(int j = 0; j < n; j++)
      cin >> board[i][j];

  while(1){
    bool flag = false;
    for(int i = 0; i < 105; i++) fill(vis[i], vis[i]+105, 0);
    queue<pair<int, int>> q;

    for(int i = 0; i < n; i++){
      for(int j = 0; j < n; j++){

        if(!vis[i][j]) q.push({i, j});
        int sum = 0;
        vector<pair<int, int>> tmp;

        while(!q.empty()){
          auto cur = q.front(); q.pop();

          for(int dir = 0; dir < 4; dir++){
            int nx = cur.X + dx[dir];
            int ny = cur.Y + dy[dir];
            if(nx < 0 || nx >= n || ny < 0 || ny >= n) continue;
            int diff = abs(board[cur.X][cur.Y] - board[nx][ny]);

            if(diff >= l && diff <= r){
              flag = 1;
              if(!vis[cur.X][cur.Y]){
                tmp.push_back({cur.X, cur.Y});
                sum += board[cur.X][cur.Y];
                vis[cur.X][cur.Y] = 1;
              }
              if(!vis[nx][ny]){
                tmp.push_back({nx, ny});
                sum += board[nx][ny];
                vis[nx][ny] = 1;
                q.push({nx,ny});
              }
            }
          }
        }
        for(int k = 0; k < tmp.size(); k++)
          board[tmp[k].X][tmp[k].Y] = sum/tmp.size();
      }
    }
    if(!flag) break;
    ans++;
  }
  cout << ans;
}