hex, binary, octal, and decimal conversions

[allenanaima]

im having a problem with this assignment, i already did the first part of the
problem which is
Take a byte, an 8 digit binary number as input, and output the corresponding
decimal number.
 Enter a decimal value, no larger than can be stored in a byte, and output the
corresponding binary and octal representations of the number.

 Enter an octal value, no larger than can be stored in a byte, and output the
corresponding decimal and binary representations.

  int main() {
        //Here i declared the variables for the first function, to use for the binary number.
        int b_1;
        int b_2;
        int b_3;
        int b_4;
        int b_5;
        int b_6;
        int b_7;
        int b_8;
        int a,b,c,d,e,f,g,h,A,B,C,D,E,F,G,H,x,y; 
                                                 
        
        cout << "Welcome! " << endl;
        cout << "To convert from binary to decimal, please have the 8bit binary number ready, and follow the instructions. " << endl;
        cout << "Please enter the first digit of your binary number (from left to right). " << endl;
        cin >> b_8 ;
        cout << "Please enter the second digit of your binary number (from left to right). " << endl;
        cin >> b_7 ;
        cout << "Please enter the third digit of your binary number (from left to right). " << endl;
        cin >> b_6 ;
        cout << "Please enter the forth digit of your binary number (from left to right). " << endl;
        cin >> b_5 ;
        cout << "Please enter the fifth digit of your binary number (from left to right). " << endl;
        cin >> b_4 ;
        cout << "Please enter the sixth digit of your binary number (from left to right). " << endl;
        cin >> b_3 ;
        cout << "Please enter the seventh digit of your binary number (from left to right). " << endl;
        cin >> b_2 ;
        cout << "Please enter the eighth digit of your binary number (from left to right). " << endl;
        cin >> b_1 ;
        
        cout << "The decimal conversion for this binary number is: " << endl;
        cout <<( (b_1 * pow(2,0)) + (b_2 * pow(2,1)) + (b_3 * pow(2,2)) + (b_4 * pow(2,3)) + (b_5 * pow(2,4)) + (b_6 * pow(2,5)) + (b_7 * pow(2,6)) + (b_8 * pow(2,7)) ) << endl;
        
        cout << "To convert from decimal to octal, and binary, please have the decimal (8-bit) number ready, and follow the instructions. " << endl;
        cout << "Please enter your decimal number: " << endl;
        cin >> dec >> x;
        cout << "The number in octal is: " << oct << x << endl; //here it converts to octal number.
a = x % 2;
        x = x / 2;
        b = x % 2;
        x = x / 2;
        c = x % 2;
        x = x / 2;
        d = x % 2;
        x = x / 2;
        e = x % 2;
        x = x / 2;
        f = x % 2;
        x = x / 2;
        g = x % 2;
        x = x / 2;
        h = x % 2;
cout << "the number in binary is: " << h << g << f << e << d << c << b << a << endl;

this is just part of the problem, but im really confused on the second part

Write a C++ program from your design in Assignment #1.
Expand the problem from Assignment #1 to work with any number of digits in the
number, as well as hexadecimal numbers:
• Ask the user for the base of the number, e.g. binary, octal, decimal, or
hexadecimal.

• Ask the user for the number of digits in the number.

• Get the number from the user.

• Print an error message if the number has more digits than the user said it would
have.

• Take the number input by the user and output all the corresponding
representations of the number other than the representation given.


any hints on point 2,3, and 4 would be greatly appreciated

[LB]

Why do you avoid using a looping structure? It will make your life easier and make your code more modular.

[allenanaima]

this was the first assignment so we still didnt take anything about loops when it was due :(