Question

java

2. Write a recursive method to return the number of occurrences a character c in a string s. c and s should be parameters.

Answer 1

CODE IN JAVA:

StringDemo.java file:

import java.util.Scanner ;
public class StringDemo {
   public static int charCount(String s, char c) {
       if(s.length() == 0)
           return 0;
       if(s.length() == 1) {
           if(s.charAt(0) == c)
               return 1;
           return 0;
       }
       if(s.charAt(0) == c)
           return 1 + charCount(s.substring(1), c);
       return charCount(s.substring(1), c);
   }
   public static void main(String[] args) {
      
       Scanner sc = new Scanner(System.in);
       System.out.print("Enter a string : ");
       String s = sc.nextLine();
       System.out.print("Enter a character : ");
       char ch = sc.next().charAt(0);
       System.out.printf("The number of occurences of %c in the string %s = %d", ch, s, charCount(s,ch));
   }

}

OUTPUT:

Problems @ Javadoc Declaration Console X <terminated > String Demo [Java Application] C:\Program FilesVava\jdk-13.0.1\bin\javaw.exe (12-Mar-2020, 1:38:27 am) Enter a string : Welcome to the world of java Enter a character :o The number of occurences of o in the string Welcome to the world of java = 4