Merge pull request #165 from AlgoLeadMe/14-jung0115

14-jung0115

jung0115/README.md

@@ -14,4 +14,5 @@
 | 10차시 | 2024.08.28.수 | 브루트포스 | [램프(1034)](https://www.acmicpc.net/problem/1034) | https://github.com/AlgoLeadMe/AlgoLeadMe-4/pull/151 |
 | 11차시 | 2024.09.04.수 | 수학 | [축구(1344)](https://www.acmicpc.net/problem/1344) | https://github.com/AlgoLeadMe/AlgoLeadMe-4/pull/153 |
 | 12차시 | 2024.09.07.토 | 다이나믹 프로그래밍 | [개근상(1563)](https://www.acmicpc.net/problem/1563) | https://github.com/AlgoLeadMe/AlgoLeadMe-4/pull/157 |
-| 13차시 | 2024.09.23.월 | 다이나믹 프로그래밍 | [사전(1256)](https://www.acmicpc.net/problem/1256) | https://github.com/AlgoLeadMe/AlgoLeadMe-4/pull/162 |
+| 13차시 | 2024.09.23.월 | 다이나믹 프로그래밍 | [사전(1256)](https://www.acmicpc.net/problem/1256) | https://github.com/AlgoLeadMe/AlgoLeadMe-4/pull/162 |
+| 14차시 | 2024.09.25.수 | 그리디 알고리즘 | [컵라면(1781)](https://www.acmicpc.net/problem/1781) | https://github.com/AlgoLeadMe/AlgoLeadMe-4/pull/165 |

jung0115/그리디알고리즘/Baekjoon_1781.java

@@ -0,0 +1,66 @@
+// 14차시 2024.09.25.수 : 백준 - 컵라면(1781)
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.StringTokenizer;
+import java.util.Arrays;
+import java.util.PriorityQueue;
+
+public class Baekjoon_1781 {
+  static class CupNoodle implements Comparable<CupNoodle> {
+    int deadLine;
+    int count;
+
+    public CupNoodle(int deadLine, int count) {
+      this.deadLine = deadLine;
+      this.count = count;
+    }
+
+    @Override
+    public int compareTo(CupNoodle o) {
+      // 데드라인을 기준으로 오름차순 정렬
+      return this.deadLine - o.deadLine;
+    }
+  }
+
+  public static void main(String[] args) throws IOException {
+    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+
+    int N = Integer.parseInt(br.readLine());
+
+    CupNoodle[] cupNoodles = new CupNoodle[N];
+
+    for (int i = 0; i < N; i++) {
+      StringTokenizer st = new StringTokenizer(br.readLine());
+
+      int deadLine = Integer.parseInt(st.nextToken()); // 데드라인
+      int count = Integer.parseInt(st.nextToken());    // 맞힐 때 받는 컵라면 수
+
+      cupNoodles[i] = new CupNoodle(deadLine, count);
+    }
+
+    // 데드라인을 기준으로 정렬 (오름차순)
+    Arrays.sort(cupNoodles);
+
+    PriorityQueue<Integer> pq = new PriorityQueue<>();
+
+    for (CupNoodle cn : cupNoodles) {
+      // 만약 현재 데드라인 내에 풀 수 있는 문제라면 큐에 추가
+      pq.offer(cn.count);
+
+      // 큐의 크기가 데드라인을 초과하면 가장 적은 컵라면 수를 제거
+      if (pq.size() > cn.deadLine) {
+        pq.poll();
+      }
+    }
+
+    int answer = 0;
+
+    // 큐에 남아 있는 컵라면의 총합을 구함
+    while (!pq.isEmpty()) {
+      answer += pq.poll();
+    }
+
+    System.out.println(answer);
+  }
+}

jung0115/그리디알고리즘/Baekjoon_1781_fail.java

@@ -0,0 +1,37 @@
+// 14차시 2024.09.25.수 : 백준 - 컵라면(1781)
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.StringTokenizer;
+import java.util.HashMap;
+import java.util.Iterator;
+
+public class Baekjoon_1781_fail {
+  public static void main(String[] args) throws IOException {
+    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+
+    int N = Integer.parseInt(br.readLine());
+
+    HashMap<Integer, Integer> cupNoodles = new HashMap<Integer, Integer>();
+
+    for(int i = 0; i < N; i++) {
+      StringTokenizer st = new StringTokenizer(br.readLine());
+
+      int deadLine = Integer.parseInt(st.nextToken()); // 데드라인
+      int count = Integer.parseInt(st.nextToken());    // 맞힐 때 받는 컵라면 수
+
+      int current = cupNoodles.getOrDefault(deadLine, 0);
+      if(current < count) cupNoodles.put(deadLine, count);
+    }
+
+    int answer = 0;
+
+    Iterator<Integer> keys = cupNoodles.keySet().iterator();
+    while(keys.hasNext()){
+      int key = keys.next();
+      answer += cupNoodles.get(key);
+    }
+
+    System.out.print(answer);
+  }
+}