From 6b12969706df0385cf895aedf0e3b7cd9a9bc83d Mon Sep 17 00:00:00 2001
From: suyeun84 <81475092+suyeun84@users.noreply.github.com>
Date: Tue, 16 Sep 2025 23:46:58 +0900
Subject: [PATCH] =?UTF-8?q?[20250916]=20PGM=20/=20LV2=20/=20N-Queen=20/=20?=
 =?UTF-8?q?=EA=B9=80=EC=88=98=EC=97=B0?=
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---
 suyeun84/202509/16 PGM LV2 N-Queen.md | 35 +++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)
 create mode 100644 suyeun84/202509/16 PGM LV2 N-Queen.md

diff --git a/suyeun84/202509/16 PGM LV2 N-Queen.md b/suyeun84/202509/16 PGM LV2 N-Queen.md
new file mode 100644
index 00000000..43eb59e4
--- /dev/null
+++ b/suyeun84/202509/16 PGM LV2 N-Queen.md	
@@ -0,0 +1,35 @@
+```java
+class Solution {
+    private static int[] board;
+    private static int answer;
+
+    public static int solution(int n) {
+        board = new int[n];
+
+        backTracking(0, n);
+
+        return answer;
+    }
+
+    private static void backTracking(int depth, int n) {
+        if (depth == n) {
+            answer++;
+            return;
+        }
+        for (int i = 0; i < n; i++) {
+            board[depth] = i;
+            if (valid(depth)) {
+                backTracking(depth + 1, n);
+            }
+        }
+    }
+
+    private static boolean valid(int i) {
+        for (int j = 0; j < i; j++) {
+            if (board[i] == board[j]) return false;
+            if (Math.abs(i - j) == Math.abs(board[i] - board[j])) return false;
+        }
+        return true;
+    }
+}
+```