From 2cc73b23e51dfaea6a84ece1e271ad0e52b4e9b8 Mon Sep 17 00:00:00 2001
From: mong3125 <mong3125@naver.com>
Date: Fri, 3 May 2024 00:07:52 +0900
Subject: [PATCH] =?UTF-8?q?=ED=94=84=EB=A1=9C=EA=B7=B8=EB=9E=98=EB=A8=B8?=
 =?UTF-8?q?=EC=8A=A4=20=EC=A0=84=ED=99=94=EB=B2=88=ED=98=B8=20=EB=AA=A9?=
 =?UTF-8?q?=EB=A1=9D=20java=20solution?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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---
 ...\355\230\270\353\252\251\353\241\235.java" | 20 +++++++++++++++++++
 1 file changed, 20 insertions(+)
 create mode 100644 "mong3125/\355\225\264\354\213\234.P_\354\240\204\355\231\224\353\262\210\355\230\270\353\252\251\353\241\235.java"

diff --git "a/mong3125/\355\225\264\354\213\234.P_\354\240\204\355\231\224\353\262\210\355\230\270\353\252\251\353\241\235.java" "b/mong3125/\355\225\264\354\213\234.P_\354\240\204\355\231\224\353\262\210\355\230\270\353\252\251\353\241\235.java"
new file mode 100644
index 0000000..ebebf49
--- /dev/null
+++ "b/mong3125/\355\225\264\354\213\234.P_\354\240\204\355\231\224\353\262\210\355\230\270\353\252\251\353\241\235.java"
@@ -0,0 +1,20 @@
+import java.util.HashSet;
+
+class Solution {
+    public boolean solution(String[] phone_book) {
+
+        HashSet<String> set = new HashSet<>();
+
+        for (String phoneNum : phone_book) {
+            set.add(phoneNum);
+        }
+
+        for (String phoneNum : phone_book) {
+            for (int i = 0; i < phoneNum.length(); i++) {
+                if (set.contains(phoneNum.substring(0, i))) return false;
+            }
+        }
+
+        return true;
+    }
+}
\ No newline at end of file