안전 영역

#include <iostream> #include <queue> #include <algorithm> #include <string.h> int N; int height[102][102]; bool visited[102][102]; std::queue<std::pair<int,int> > q; int dx[4] = {0, 0, 1, -1}; int dy[4] = {1, -1, 0, 0}; int ans; void input_faster() { std::ios_base::sync_with_stdio(false); std::cin.tie(0); std::cout.tie(0); } void input() { input_faster(); std::cin >> N; for (int i = 0 ; i < N ; i++) for (int j = 0 ; j < N ; j++) std::cin >> height[i][j]; ans = 1; } bool bfs(int b_height) { int x, y, q_x, q_y, cnt; cnt = 0; memset(visited, 0, sizeof(visited)); q = std::queue<std::pair<int, int> >(); for(int i = 0 ; i < N ; i++) { for (int j = 0 ; j < N ; j++) { if (visited[i][j] || height[i][j] <= b_height) continue; cnt++; q.push({i, j}); visited[i][j] = 1; while(!q.empty()) { y = q.front().first; x = q.front().second; q.pop(); for (int k = 0 ; k < 4 ; k++) { q_y = y + dy[k]; q_x = x + dx[k]; if (q_y < 0 || q_x < 0 || q_y >= N || q_x >= N || visited[q_y][q_x] || height[q_y][q_x] <= b_height) continue; visited[q_y][q_x] = 1; q.push({q_y, q_x}); } } } } if (!cnt) return (0); ans = std::max(ans, cnt); return (1); } void solve() { int i = 0; while (++i <= 100 && bfs(i)) ; } void print_val() { std::cout << ans; } int main() { input(); solve(); print_val(); return (0); }