C++ Different Digits In a distant country, a queen is very superstitious and does not like numbers with repeated digits like 77, 434 or 2121. Thus, she declares any house street number with repeated digits to be invalid. You have been appointed by Her Majesty to write a program that, given two integers a and b, determines the maximum number of valid house street numbers between a and b, inclusive.
Examples:
For a = 3 and b = 12, the answer is 9.
For a = 12 and b = 34, the answer is 21.
You cannot use string variables in this assignment.
The Input is given by two integers a and b such that 0 < a <= b <= 10000
Your code should check if the input is given as specified: the numbers are positive integers, the second one is greater than or equal to the first, and so on. If the input does not meet the requirements, the output should be "Invalid input".
Your program must define and use the following function: int countDigitOccurrences (int n, int digit)
This function has as input parameters a positive integer n that is in the range and
0 <= digit <= 9, and returns how many times the digit occurs in the number n. This function must be submitted in a separate file functions. cpp along with the corresponding header file functions. h with the declaration of this function. This header file must be included at the beginning of differentdigits. cpp and functions. cpp. So, the file begins with:
#include
#include "functions. h"