4.How to remove duplicate Characters from a String in java.

Description:

Write a sample code to remove duplicate Characters from a String.

Code:

? 1 2 3 4 5 6 7 8 9 10 import java.util.HashSet; import java.util.Set; public class RemoveDuplicate { public static void main(String[] args) { String str = "godblessgovind"; char[] characters = str.toCharArray(); Set set = new HashSet(); StringBuilder sb = new StringBuilder(); System.out.println("String with duplicates : " + str); for (char c : characters) { if (!set.contains(c)) { set.add(c); sb.append(c); } } System.out.println("String after duplicates removed : " + sb.toString()); } }

Output:

String with duplicates : godblessgovind String after duplicates removed : godblesvin

3.How to print all map values in java.

Description:

Write a sample code to print all map values.

Code:

? 1 2 3 4 5 6 7 8 9 10 import java.util.Collection; import java.util.HashMap; import java.util.Iterator; import java.util.Map; public class PrintMapvalue { public static void main(String[] args) { HashMap<String, String> hmap = new HashMap<String, String>(); hmap.put("1000", "God"); hmap.put("2000", "Bless"); hmap.put("3000", "Govind"); Collection c = hmap.values(); Iterator itr = c.iterator(); while (itr.hasNext()) { System.out.println(itr.next()); } } }

Output:

God Bless Govind

2. Count occurrences of character in string java using hashmap

Description:

Write a sample code to Count occurrences of character in string.

Code:

? 1 2 3 4 5 6 7 8 9 10 import java.util.HashMap; public class NO_of_Occurance { public static void main(String[] args) { String str = "Programming"; HashMap<Character, Integer> map = new HashMap<>(); for (char ch : str.toCharArray()) { if (map.containsKey(ch)) { int val = map.get(ch); map.put(ch, val + 1); } else { map.put(ch, 1); } } System.out.println(map); } }

Output:

{P=1, a=1, r=2, g=2, i=1, m=2, n=1, o=1}

1. How to find Reverse Sting in java.

Description:

Write a sample code to reverse String.

Code:

? 1 2 3 4 5 6 7 8  import java.util.Scanner; public class ReverseString { public static void main(String[] args) { String Original, reverse = " "; Scanner s = new Scanner(System.in); System.out.println("Enter String for reverse:"); Original = s.nextLine(); int length = Original.length(); for (int i = length - 1; i >= 0; i--) reverse = reverse + Original.charAt(i); System.out.println("Rverse of entered String is:" + reverse); } }

Input: Enter String for reverse: godblessgovind Output:

Rverse of entered String is: dnivogsselbdog