Write a program that converts a number from one base to another base for the following cases:

Binary to Decimal/Decimal to Binary

Binary to Octal/Octal to Binary

Binary to Hexadecimal/Hexadecimal to Binary

The program should contain functions for each of these base conversions. Each function should take an array of characters representing the initial number and return an array of characters representing the final number.

Language is in C++. In particular, The program should use pointer syntax for arrays and not use the bracket notation.