[20250808] BOJ / G4 / 가장 큰 정사각형 / 이종환

Author: 0224LJH

0224LJH/202508/8 BOJ 가장 큰 정사각형.md

@@ -0,0 +1,60 @@
+```java
+import java.awt.*;
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.*;
+
+public class Main {
+    static int height, width;
+    static int[][] arr;
+    static int[][] dp;
+
+    public static void main(String[] args) throws IOException {
+        init();
+        int result = process();
+        System.out.println(result * result);
+    }
+
+    private static void init() throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        height = Integer.parseInt(st.nextToken());
+        width = Integer.parseInt(st.nextToken());
+
+        arr = new int[height][width];
+        dp = new int[height][width];
+
+        for (int i = 0; i < height; i++) {
+            String[] input = br.readLine().split("");
+            for (int j = 0; j < width; j++) {
+                arr[i][j] = Integer.parseInt(input[j]);
+            }
+        }
+    }
+
+    private static int process() {
+        int maxSize = 0;
+
+        // DP 초기화 및 계산
+        for (int i = 0; i < height; i++) {
+            for (int j = 0; j < width; j++) {
+                if (arr[i][j] == 1) {
+                    if (i == 0 || j == 0) {
+                        dp[i][j] = 1;
+                    } else {
+                        //  왼쪽, 위쪽, 대각선 위쪽의 최솟값 + 1
+                        dp[i][j] = Math.min(dp[i-1][j],
+                                Math.min(dp[i][j-1], dp[i-1][j-1])) + 1;
+                    }
+                    maxSize = Math.max(maxSize, dp[i][j]);
+                } else {
+                    dp[i][j] = 0;
+                }
+            }
+        }
+
+        return maxSize;
+    }
+}
+```