HOW TO COUNT OCCURRENCE OF THE WORDS IN STRING  (It can also be solved by using nested for loops...)  String str = "I am happy and why not and why are you not happy you should be"    String [] arr = str.split(" ");    Map<String, Integer> map = new HashMap<>();     for (int i=0 ; i < arr.length ; i++){        if (!map.containsKey(arr[i])){             map.put(arr[i],1);            } else{          map.put(arr[i],map.get(arr[i])+1);         }         }      for(Map.Entry<String, Integer> each : map.entrySet()){      System.out.println(each.getKey()+" occures " + each.getValue() + " times");     }

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