Week10 김명진 통학버스 2513 풀이

src/week10/tonghagbus2513/Main.java

@@ -1,5 +1,105 @@
 package week10.tonghagbus2513;
 
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.PriorityQueue;
+import java.util.StringTokenizer;
+
+
+class Bus {
+    int maxStudent;
+    int currStudent;
+
+    public Bus(int maxStudent, int currStudent) {
+        this.maxStudent = maxStudent;
+        this.currStudent = currStudent;
+    }
+
+}
+
+class AptPoint implements Comparable<AptPoint> {
+    int studentNum;
+    int dist;
+    int point;
+
+    public AptPoint(int studentNum, int dist, int point) {
+        this.studentNum = studentNum;
+        this.dist = dist;
+        this.point = point;
+    }
+
+    @Override
+    public int compareTo(AptPoint o) {
+        return o.dist - this.dist;
+    }
+}
+
 public class Main {
+    static int N, K, S;
+    static PriorityQueue<AptPoint> left;
+    static PriorityQueue<AptPoint> right;
+    static Bus bus;
+
+    public static void main(String[] args) throws IOException {
+        //System.setIn(new FileInputStream("resources/study/week10/BJ2513/input2.txt"));
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        N = Integer.parseInt(st.nextToken()); // 지점수
+        K = Integer.parseInt(st.nextToken()); // 인원수
+        S = Integer.parseInt(st.nextToken()); // 학교위치
+        left = new PriorityQueue<>();
+        right = new PriorityQueue<>();
+        bus = new Bus(K, 0);
+        for (int row = 0; row < N; row++) {
+            st = new StringTokenizer(br.readLine());
+            int point = Integer.parseInt(st.nextToken());
+            int student = Integer.parseInt(st.nextToken());
+            int dist = Math.abs(S - point);
+            if (point < S) {
+                // 왼쪽에 있다
+                left.offer(new AptPoint(student, dist, point));
+            } else {
+                // 오른쪽에 있다
+                right.offer(new AptPoint(student, dist, point));
+            }
+        }
+
+        int lDIst = countDist(left);
+        int RDIst = countDist(right);
+        System.out.println((lDIst + RDIst));
+
+
+    }
+
+    private static int countDist(PriorityQueue<AptPoint> pq) {
+        int totalDist = 0;
+        while (!pq.isEmpty()) {
+            AptPoint curStop = pq.poll();
+            int repeatCount = curStop.studentNum / bus.maxStudent; // 반복해야하는 횟수
+            if (curStop.studentNum % bus.maxStudent > 0) repeatCount++; // 나머지가 있다면 한번더 올수 있는거다
+            // 태울수 있는 버스인원 = 왕복하면서 태운 학생수 - 현재 정류장인원
+            // 만약 10 인데 4인버스라면 3번간다 (12) - 현재 정류장인웡 = 버스내의 승객은 2명더태울수 있다.
+            int remainStudent = bus.maxStudent * repeatCount - curStop.studentNum;
+            while (!pq.isEmpty()) {
+                // 다음 정류장을 돌면서 더태울수 있는지 탐색한다.
+                AptPoint next = pq.poll();
+                // 태울수 있는 인원수가 더많으면
+                if (next.studentNum <= remainStudent) {
+                    //버스에 태운다
+                    remainStudent -= next.studentNum;
+                } else {
+                    // 태울수 있는 인원이 다음 역보다 적으면
+                    // 남은 승객수만큼만 태우고 다시온다
+                    next.studentNum -= remainStudent;
+                    pq.add(next);
+                    break;
+                }
+            }
+            totalDist += (2 * repeatCount * curStop.dist);
+        }
+        return totalDist;
+    }
+
 
 }