From c09465f64df8c36b6befeb8579877c28e3d61a86 Mon Sep 17 00:00:00 2001
From: lkhyun <102892446+lkhyun@users.noreply.github.com>
Date: Sun, 23 Nov 2025 18:45:44 +0900
Subject: [PATCH] =?UTF-8?q?[20251123]=20PGM=20/=20Lv2=20/=20=EC=86=8C?=
 =?UTF-8?q?=EC=88=98=20=EC=B0=BE=EA=B8=B0=20/=20=EC=9D=B4=EA=B0=95?=
 =?UTF-8?q?=ED=98=84?=
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---
 ...4\354\210\230 \354\260\276\352\270\260.md" | 53 +++++++++++++++++++
 1 file changed, 53 insertions(+)
 create mode 100644 "lkhyun/202511/23 PGM Lv2 \354\206\214\354\210\230 \354\260\276\352\270\260.md"

diff --git "a/lkhyun/202511/23 PGM Lv2 \354\206\214\354\210\230 \354\260\276\352\270\260.md" "b/lkhyun/202511/23 PGM Lv2 \354\206\214\354\210\230 \354\260\276\352\270\260.md"
new file mode 100644
index 00000000..c6742d5f
--- /dev/null
+++ "b/lkhyun/202511/23 PGM Lv2 \354\206\214\354\210\230 \354\260\276\352\270\260.md"	
@@ -0,0 +1,53 @@
+```java
+import java.util.*;
+class Solution {
+    static int[] number;
+    static boolean[] visited;
+    static int len;
+    static Set<Integer> primes = new HashSet<>();
+    
+    public int solution(String numbers) {
+        len = numbers.length();
+        number = new int[len];
+        visited = new boolean[len];
+        primes.clear();
+        
+        for(int i = 0; i < len; i++){
+            number[i] = Character.getNumericValue(numbers.charAt(i));
+        }
+        
+        findPrime(new StringBuilder());
+        return primes.size();
+    }
+    
+    public static void findPrime(StringBuilder sb){
+        if(sb.length() > 0){
+            int num = Integer.parseInt(sb.toString());
+            if(isPrime(num)){
+                primes.add(num);
+            }
+        }
+        
+        for(int i = 0; i < len; i++){
+            if(!visited[i]){
+                visited[i] = true;
+                sb.append(number[i]);
+                findPrime(sb);
+                sb.deleteCharAt(sb.length() - 1);
+                visited[i] = false;
+            }
+        }
+    }
+    
+    public static boolean isPrime(int num){
+        if(num < 2) return false;
+        if(num == 2) return true;
+        if(num % 2 == 0) return false;
+        
+        for(int i = 3; i * i <= num; i += 2){
+            if(num % i == 0) return false;
+        }
+        return true;
+    }
+}
+```