32-kokeunho

kokeunho/README.md

@@ -32,4 +32,5 @@
 | 29차시 | 2025.07.21 | 그래프 탐색 | [불!](https://www.acmicpc.net/problem/4179) |[#118](https://github.com/AlgoLeadMe/AlgoLeadMe-12/pull/118) |
 | 30차시 | 2025.07.26 | 그래프 탐색 | [중량제한](https://www.acmicpc.net/problem/1939) |[#120](https://github.com/AlgoLeadMe/AlgoLeadMe-12/pull/120) |
 | 31차시 | 2025.08.03 | 그래프 탐색 | [면접보는 승범이네](https://www.acmicpc.net/problem/17835) | [#126](https://github.com/AlgoLeadMe/AlgoLeadMe-12/pull/126) |
+| 32차시 | 2025.08.10 | 그래프 탐색 | [석유 시추](https://school.programmers.co.kr/learn/courses/30/lessons/250136) |[#129](https://github.com/AlgoLeadMe/AlgoLeadMe-12/pull/129) |
 ---

kokeunho/그래프 탐색/32-kokeunho.java

@@ -0,0 +1,57 @@
+import java.util.*;
+
+class Solution {
+    static int col, row;
+    static int[] dx = {-1, 1, 0, 0};
+    static int[] dy = {0, 0, -1, 1};
+    static int[] sumAreaPerCol;
+    static boolean[][] visited;
+
+    public int solution(int[][] land) {
+        col = land[0].length;
+        row = land.length;
+        sumAreaPerCol = new int[col];
+        visited = new boolean[row][col];
+
+        for (int i = 0; i < col; i++) {
+            for (int j = 0; j < row; j++) {
+                if (land[j][i] == 1 && !visited[j][i]) {
+                    bfs(j, i, land);
+                }
+            }
+        }
+
+        int maxArea = 0;
+        for (int i = 0; i < col; i++) {
+            maxArea = Math.max(maxArea, sumAreaPerCol[i]);
+        }
+        return maxArea;
+    }
+    public void bfs(int x, int y, int[][] land) {
+        Queue<int[]> queue = new LinkedList<>();
+        queue.add(new int[]{x, y});
+        visited[x][y] = true;
+        int area = 1;
+        Set<Integer> colList = new HashSet<>();
+        colList.add(y);
+
+        while(!queue.isEmpty()) {
+            int[] current = queue.poll();
+
+            for (int i = 0; i < 4; i++) {
+                int nx = current[0] + dx[i];
+                int ny = current[1] + dy[i];
+                if (nx >= 0 && nx < row && ny >= 0 && ny < col && !visited[nx][ny] && land[nx][ny] == 1) {
+                    queue.add(new int[]{nx, ny});
+                    visited[nx][ny] = true;
+                    area++;
+                    colList.add(ny);
+                }
+            }
+        }
+
+        for (int column : colList) {
+            sumAreaPerCol[column] += area;
+        }
+    }
+}