C++ Inheritance to convert an Octal number to a Decimal number without using an array

Octal to Decimal number program in C++

Write a program in C++ to convert an Octal number to a Decimal number without using an array by using the single inheritance.

WAP in C++ to convert an Octal number to a Decimal number without using an array by using the multiple inheritances.

 

Write a C++ program to convert an Octal to a Decimal number by using the multi-level inheritance.