From c82a5324e22d5a9ed59e4d328bea5f6d70d741c3 Mon Sep 17 00:00:00 2001
From: mordiumaco <mordiumaco@gmail.com>
Date: Thu, 16 Jul 2020 01:16:32 +0900
Subject: [PATCH] =?UTF-8?q?1-8=20=EC=99=84=EC=A3=BC=ED=95=98=EC=A7=80?=
 =?UTF-8?q?=EB=AA=BB=ED=95=9C=20=EC=84=A0=EC=88=98?=
MIME-Version: 1.0
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---
 .../Solution.java"                            | 53 +++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git "a/week2/1. \354\231\204\354\243\274\355\225\230\354\247\200 \353\252\273\355\225\234 \354\204\240\354\210\230/Solution.java" "b/week2/1. \354\231\204\354\243\274\355\225\230\354\247\200 \353\252\273\355\225\234 \354\204\240\354\210\230/Solution.java"
index 23d7824..172f2b2 100644
--- "a/week2/1. \354\231\204\354\243\274\355\225\230\354\247\200 \353\252\273\355\225\234 \354\204\240\354\210\230/Solution.java"	
+++ "b/week2/1. \354\231\204\354\243\274\355\225\230\354\247\200 \353\252\273\355\225\234 \354\204\240\354\210\230/Solution.java"	
@@ -1,7 +1,60 @@
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.Map.Entry;
+
 /*
     1. 완주하지 못한 선수
     https://programmers.co.kr/learn/courses/30/lessons/42576
 */
 public class Solution {
+    public static void main(String[] args) {
+
+        String[] participant = { "leo", "kiki", "eden" };
+        String[] completion = { "eden", "kiki" };
+
+        System.out.println(solution(participant, completion));
+        System.out.println(solution2(participant, completion));
+    }
+
+    public static String solution(String[] participant, String[] completion) {
+
+        Arrays.sort(participant);
+        Arrays.sort(completion);
+
+        for (int i = 0; i < completion.length; i++) {
+            if (!participant[i].equals(completion[i])) {
+                return participant[i];
+            }
+        }
+
+        return participant[participant.length - 1];
+    }
+
+    public static String solution2(String[] participant, String[] completion) {
+
+        Map<String, Integer> checkerMap = new HashMap<>();
+
+        for (String person : participant) {
+            checkerMap.put(person, checkerMap.getOrDefault(person, 0) + 1);
+        }
+
+        for (String person : completion) {
+            checkerMap.put(person, checkerMap.getOrDefault(person, 0) - 1);
+        }
+
+        Iterator<Entry<String, Integer>> it = checkerMap.entrySet().iterator();
+
+        while (it.hasNext()) {
+
+            Entry<String, Integer> mapEntry = it.next();
+
+            if (mapEntry.getValue() == 1) {
+                return mapEntry.getKey();
+            }
+        }
 
+        return null;
+    }
 }
\ No newline at end of file