Your task is to write a method countSevens that counts the number of digits equal to 7 in a given number. For example, the call countSevens(1797) should return 2 since the number contains two digits 7.

Hint: Repeatedly compute % 10 and / 10.

Complete the following code:

public class Numbers
{
   /**
      Counts the number of digits with value 7 in a given number
      @param n any non-negative number
      @return the number of digits with value 7 in the decimal representation of n
   */
   public int countSevens(int n)
   {
      // your work here
   
   
   
   
   
   
   }
}

Complete the following file:

Numbers.java