2024-03-18

BOJ-ios/README.md

@@ -1,6 +1,7 @@
-## ✏️ 기록   
+## ✏️ 기록
+
+| 차시  |    날짜    | 문제유형 |                         링크                          |                           풀이                           |
+| :---: | :--------: | :------: | :---------------------------------------------------: | :------------------------------------------------------: |
+| 1차시 | 2024.03.18 |  트라이  | [전화번호 목록](https://www.acmicpc.net/problem/5052) | [#2](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pulls/2) |
 
-| 차시 |    날짜    | 문제유형 | 링크 | 풀이 |
-|:----:|:---------:|:----:|:-----:|:----:|
-| 1차시 | 2023.10.27 |  BFS  | -  | - |
 ---

BOJ-ios/트라이/P5052번_전화번호_목록/Main.java

@@ -0,0 +1,55 @@
+package BAEKJOON.Gold.Gold_IV.P5052번_전화번호_목록;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.Arrays;
+
+public class Main {
+    public static class Contact {
+        Contact[] contacts;
+        boolean exists;
+
+        Contact() {
+            contacts = new Contact[10];
+        }
+
+        public boolean addContacts(String phoneNumber) {
+            int digit = phoneNumber.charAt(0) - '0';
+            if (this.contacts[digit] == null) {
+                this.contacts[digit] = new Contact();
+            } else if (this.contacts[digit].exists) {
+                return false;
+            }
+            if (phoneNumber.length() == 1) {
+                this.contacts[digit].exists = true;
+            } else {
+                return this.contacts[digit].addContacts(phoneNumber.substring(1, phoneNumber.length()));
+            }
+            return true;
+        }
+    }
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        int T = Integer.parseInt(br.readLine());
+        StringBuilder sb = new StringBuilder();
+        for (int i = 0; i < T; i++) {
+            Contact root = new Contact();
+            int N = Integer.parseInt(br.readLine());
+            String[] numbers = new String[N];
+            for (int j = 0; j < N; j++)
+                numbers[j] = br.readLine();
+            Arrays.sort(numbers);
+            boolean able = true;
+            for (int j = 0; j < N; j++) {
+                if (!root.addContacts(numbers[j])) {
+                    able = false;
+                    break;
+                }
+            }
+            sb.append(able ? "YES" : "NO").append('\n');
+        }
+        System.out.print(sb.toString());
+    }
+}