2022-08-18 update: added "Reduce Array Size to The Half" (#70)

Author: fartem

src/main/java/com/smlnskgmail/jaman/leetcodejava/medium/ReduceArraySizeToTheHalf.java

@@ -0,0 +1,36 @@
+package com.smlnskgmail.jaman.leetcodejava.medium;
+
+import java.util.*;
+
+// https://leetcode.com/problems/reduce-array-size-to-the-half/
+public class ReduceArraySizeToTheHalf {
+
+    private final int[] input;
+
+    public ReduceArraySizeToTheHalf(int[] input) {
+        this.input = input;
+    }
+
+    public int solution() {
+        int n = input.length;
+        if (n < 3) {
+            return 1;
+        }
+        Map<Integer, Integer> m = new HashMap<>();
+        for (int num : input) {
+            m.put(num, m.getOrDefault(num, 0) + 1);
+        }
+        Queue<Integer> q = new PriorityQueue<>(Collections.reverseOrder());
+        for (int num : m.values()) {
+            q.offer(num);
+        }
+        int r = 0;
+        int result = 0;
+        while (r < n / 2 && q.size() > 0) {
+            r += q.poll();
+            result++;
+        }
+        return result;
+    }
+
+}

src/test/java/com/smlnskgmail/jaman/leetcodejava/medium/ReduceArraySizeToTheHalfTest.java

@@ -0,0 +1,17 @@
+package com.smlnskgmail.jaman.leetcodejava.medium;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class ReduceArraySizeToTheHalfTest {
+
+    @Test
+    public void defaultTest() {
+        assertEquals(
+                2,
+                new ReduceArraySizeToTheHalf(new int[]{3, 3, 3, 3, 5, 5, 5, 2, 2, 7}).solution()
+        );
+    }
+
+}