[BOJ 2468] 안전 영역

src/week2/BOJ2468/BOJ2468_V1.cpp

@@ -0,0 +1,61 @@
+#include <bits/stdc++.h>
+using namespace std;
+vector<vector<int>> space;
+vector<vector<int>> visited;
+int N;
+int dy[4] = {-1, 0, 1, 0};
+int dx[4] = {0, 1, 0, -1};
+
+void dfs(int y, int x, int water){
+    visited[y][x] = 1;
+
+    for (int i = 0; i < 4; i++) {
+        int ny = y + dy[i];
+        int nx = x + dx[i];
+
+        if (ny < 0 || nx < 0 || ny >= N || nx >= N || visited[ny][nx] || space[ny][nx] <= water) continue;
+
+        dfs(ny, nx, water);
+    }
+}
+int main() {
+
+    ios_base::sync_with_stdio(false);
+    cin.tie(NULL);
+    cout.tie(NULL);
+
+    cin >> N;
+    int max_val = -1;
+    for (int i = 0; i < N; i++) {
+        space.push_back(vector<int>());
+        visited.push_back(vector<int>());
+        for (int j = 0; j < N; j++) {
+            int temp;
+            cin >> temp;
+            if (temp > max_val) max_val = temp;
+            space[i].push_back(temp);
+            visited[i].push_back(0);
+        }
+    }
+
+
+    int max_cnt = -1;
+    for (int k=0; k <= max_val; k++) {
+        int cnt = 0;
+        for (int i = 0; i < N; i++) {
+            for (int j = 0; j < N; j++) {
+                if (space[i][j] > k && !visited[i][j]) {
+                    dfs(i, j, k);
+                    cnt++;
+                }
+            }
+        }
+        if (cnt > max_cnt) max_cnt = cnt;
+        fill(visited.begin(), visited.end(), vector<int>(N,0));
+    }
+
+
+    cout << max_cnt << '\n';
+
+    return 0;
+}