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 file:

Numbers.java

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 } }