[20260206] BOJ / P5 / 비숍 / 이준희

JHLEE325/202602/06 BOJ P5 비숍.md

@@ -0,0 +1,55 @@
+```java
+import java.io.*;
+import java.util.*;
+
+public class Main {
+
+    static int n;
+    static int[][] board;
+    static boolean[] diag1;
+    static boolean[] diag2;
+    static int[] maxCount = new int[2]; // 0: 검은색, 1: 흰색
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        n = Integer.parseInt(br.readLine());
+        board = new int[n][n];
+
+        diag1 = new boolean[2 * n];
+        diag2 = new boolean[2 * n];
+
+        for (int i = 0; i < n; i++) {
+            StringTokenizer st = new StringTokenizer(br.readLine());
+            for (int j = 0; j < n; j++) {
+                board[i][j] = Integer.parseInt(st.nextToken());
+            }
+        }
+
+        backtracking(0, 0, 0, 0);
+        backtracking(0, 1, 0, 1);
+
+        System.out.println(maxCount[0] + maxCount[1]);
+    }
+
+    static void backtracking(int r, int c, int count, int color) {
+        maxCount[color] = Math.max(maxCount[color], count);
+
+        if (c >= n) {
+            r++;
+            c = (c % 2 == 0) ? 1 : 0;
+        }
+
+        if (r >= n) return;
+
+        if (board[r][c] == 1 && !diag1[r + c] && !diag2[r - c + n]) {
+            diag1[r + c] = true;
+            diag2[r - c + n] = true;
+            backtracking(r, c + 2, count + 1, color);
+            diag1[r + c] = false;
+            diag2[r - c + n] = false;
+        }
+
+        backtracking(r, c + 2, count, color);
+    }
+}
+```