Paired colors

MatchColors/MatchPairedColors.java

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+import java.util.HashMap;
+
+/**
+ * MatchPairedColors
+ */
+public class MatchPairedColors {
+
+  public static void main(String[] args) {
+
+    int[] ar = { 1, 1, 1, 1, 3, 2, 2, 3, 4 };
+    System.out.println(numberOfPairedSocks(ar));
+  }
+
+  private static int numberOfPairedSocks(int[] arr) {
+    int numofP = 0;
+    HashMap<Integer, Integer> socksCount = new HashMap<>();
+    for (int sock : arr) {
+      if (socksCount.containsKey(sock)) {
+        socksCount.put(sock, socksCount.get(sock) + 1);
+      } else {
+        socksCount.put(sock, 1);
+      }
+    }
+
+    for (int count : socksCount.values()) {
+      numofP += count / 2;
+    }
+    return numofP;
+  }
+}