Add PT1.java

Author: seanprashad

Miscellaneous/PT1.java

@@ -0,0 +1,55 @@
+import java.util.*;
+
+class PinSystem {
+    class Pin {
+        int id;
+        double score;
+
+        public Pin(int id, double score) {
+            this.id = id;
+            this.score = score;
+        }
+    }
+
+    Map<String, PriorityQueue<Pin>> hm;
+    Set<Integer> usedIds;
+
+    public PinSystem() {
+        hm = new HashMap<>();
+        usedIds = new HashSet<>();
+    }
+
+    public boolean addPin(int id, double score, String type) {
+        if (usedIds.contains(id)) {
+            return false;
+        }
+
+        hm.putIfAbsent(type, new PriorityQueue<Pin>((p1, p2) -> Double.compare(p2.score, p1.score)));
+        hm.get(type).offer(new Pin(id, score));
+        return usedIds.add(id);
+    }
+
+    public List<Integer> getTopK(String type, int k) {
+        if (!hm.containsKey(type)) {
+            return Collections.emptyList();
+        }
+
+        PriorityQueue<Pin> pins = hm.get(type);
+        List<Pin> polledPins = new ArrayList<>();
+        List<Integer> result = new ArrayList<>(k);
+
+        k = Math.min(k, pins.size());
+
+        while (k > 0) {
+            polledPins.add(pins.poll());
+            --k;
+        }
+
+        for (Pin p : polledPins) {
+            result.add(p.id);
+            pins.offer(p);
+        }
+
+        return result;
+    }
+}