Add all the A tasks

Task/Associative-array-Iteration/Java/associative-array-iteration.java

@@ -0,0 +1,21 @@
+Map<String, Integer> myDict = new HashMap<String, Integer>();
+myDict.put("hello", 1);
+myDict.put("world", 2);
+myDict.put("!", 3);
+
+// iterating over key-value pairs:
+for (Map.Entry<String, Integer> e : myDict.entrySet()) {
+    String key = e.getKey();
+    Integer value = e.getValue();
+    System.out.println("key = " + key + ", value = " + value);
+}
+
+// iterating over keys:
+for (String key : myDict.keySet()) {
+    System.out.println("key = " + key);
+}
+
+// iterating over values:
+for (Integer value : myDict.values()) {
+    System.out.println("value = " + value);
+}