[BOJ 2234] 성곽

src/week4/BOJ2234/BOJ2234_V1.cpp

@@ -0,0 +1,72 @@
+#include <bits/stdc++.h>
+using namespace std;
+int inp[50][50];
+int room_num[50][50];
+int N,M;
+bool visited[50][50];
+int dy[4] = {0,-1,0,1};
+int dx[4] = {-1,0,1,0};
+int ret[3];
+vector<int> room_size;
+int dfs(int y, int x, int rn) {
+    int ret_val = 1;
+    for (int i=0; i<4; i++) {
+        int ny = dy[i] + y;
+        int nx = dx[i] + x;
+        if (ny < 0 || nx < 0 || ny >= N || nx >= M || visited[ny][nx]) continue;
+        if (inp[y][x] & (1 << i)) continue;
+        visited[ny][nx] = true;
+        room_num[ny][nx] = rn;
+        ret_val += dfs(ny, nx, rn);
+    }
+
+    return ret_val;
+}
+int main() {
+
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+    cout.tie(nullptr);
+
+    cin >> M >> N;
+
+    for (int i=0; i<N; i++) {
+        for (int j=0; j<M; j++) {
+            cin >> inp[i][j];
+        }
+    }
+
+    for (int i=0; i<N; i++) {
+        for (int j=0; j<M; j++) {
+            if (!visited[i][j]) {
+                visited[i][j] = true;
+                room_num[i][j] = ret[0];
+                int room = dfs(i, j, ret[0]);
+                ret[0]++;
+                room_size.push_back(room);
+                ret[1] = max(ret[1], room);
+            }
+        }
+    }
+
+    for (int i=0; i<N; i++) {
+        for (int j=0; j<M; j++) {
+            for (int k=0; k<4; k++) {
+                int ny = i + dy[k];
+                int nx = j + dx[k];
+                if (ny < 0 || nx < 0 || ny >= N || nx >= M) continue;
+                if (!(inp[i][j] & (1 << k))) continue;
+                int room_a = room_num[ny][nx];
+                int room_b = room_num[i][j];
+                if (room_a == room_b) continue;
+                ret[2] = max(ret[2], room_size[room_a] + room_size[room_b]);
+            }
+        }
+    }
+
+    for (int i=0; i<3; i++) {
+        cout << ret[i] << '\n';
+    }
+
+    return 0;
+}