Add hackerrank problem on Hashmap to Contributors list

Hackerrank/Hashmap.java

@@ -0,0 +1,30 @@
+
+//Complete this code or write your own from scratch
+import java.util.*;
+import java.io.*;
+
+class Hashmap{
+   public static void main(String []argh)
+   {
+      Scanner x = new Scanner(System.in);
+      int n=x.nextInt();
+      x.nextLine();
+      Map<String, Integer> map = new HashMap<String, Integer>();
+      for(int i=0;i<n;i++)
+      {
+          String name = x.next();
+          int phone = x.nextInt();
+          x.nextLine();
+         map.put(name, phone);
+      }
+      while(x.hasNext())
+      {
+         String s=x.nextLine();
+         if (map.get(s) != null) {
+             System.out.println(s+"="+map.get(s));
+         } else {
+             System.out.println("Not found");
+         }
+      }
+   }
+}