Java Program to find Duplicate Character In String ?

Previously We have discussed The program for

Java Program to Reverse Numbers ?

Here we learn the Program for counting the Duplicate character from String using HashMap class and Set Interface.

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import java.util.HashMap; import java.util.Map; import java.util.Set; public class DuplicateCharacterFromString { public static void method(String str){ Map<Character, Integer> map = new HashMap<>(); for(int i=0;i<str.length();i++){ if(map.containsKey(str.charAt(i))){ map.put(str.charAt(i), map.get(str.charAt(i))+1); } else{ map.put(str.charAt(i), 1); } } Set<Character> set = map.keySet(); for(Character c : set){ if(map.get(c) > 1){ System.out.println("Duplicate Character : "+c+" Occurence "+map.get(c)); } } } public static void main(String[] args) { DuplicateCharacterFromString.method("abca"); } }

Output:

Duplicate Character : a Occurence 2

      

Blog Author - Pushkar Khosla,
Software Developer by Profession with 3.0 Yrs of Experience , through this blog i'am sharing my industrial Java Knowledge to entire world. For any question or query any one can comment below or mail me at pushkar.itsitm52@gmail.com.

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