Java: In an integer, count the number of digits with value 2

Java Method: Exercise-17 with Solution

Count Occurrences of Digit '2' in Integer

Write a Java method to count the number of digits in an integer with the value 2. The integer may be assumed to be non-negative.

Pictorial Presentation:

Sample:
Input: 12541
Output: 1
Input: 25672
Output: 2
Input: 9484
Output: 0

Sample Solution:

Java Code:

import java.util.Scanner;
public class Main {
 public static void main(String[] args)
   {
       Scanner in = new Scanner(System.in);
       System.out.print("Input a number: ");
       int n = in.nextInt();
       if (n>0)
       {
       System.out.println(test(n));
       }
   }
 public static int test(int num)
   {
    int ctr = 0;
    int n = num;
    do{
      if (n % 10 == 2){
          ctr ++;
      }
      n /= 10;
     }while(n > 0);
      return ctr;
   }
}

Sample Output:

Input a number:  12541
1

Flowchart :

Java Code Editor:

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