Question

Make a simple C++ program not complex

1. Any number is entered from keyboard of base 2, base 8, base 10 or base 16.
2. Program asks for conversion options (menu) to convert into required base, i.e., 2, 8, 10 or 16.
3. User selects the option and program converts the input number to the selected base number.
4. Output number is shown on the screen.

Following points are to be considered while making the program:

• It should be a menu driven program, use switch/case for menu. Program must have following options:
  Select Input Number Base
  1 for Binary
  2 for Octal
  3 for Decimal
  4 for Hexadecimal
  5 for Exit
  
  When user selects option from 1 to 5, User inputs the number.
  After number is entered, program displays following menu:
  1 for conversion to Binary
  2 for conversion to Octal
  3 for conversion to Decimal
  4 for converesion to Hexadecimal
  5 for Exit
  
  After user input, the program converts the input number to the given base, and displays the result.
• After number display, pressing any key will again takes back to the first menu for input number.
• Program should run until and unless user presses EXIT.

Answer 1

Step 1 : Save the following code in Conversion.cpp

#include <iostream>
#include <string>
using namespace std;

int main() {
int fromBase;
int toBase;
int input;
string binary;
while (true) {
// Display menu
cout << "Select Input Number Base" << endl;
cout << "1 for Binary" << endl;
cout << "2 for Octal" << endl;
cout << "3 for Decimal" << endl;
cout << "4 for Hexadecimal" << endl;
cout << "5 for Exit" << endl;
cin >> fromBase;
if (5 == fromBase) {
return 0;
}
cout << "Enter the number : ";
// For binary read string and use stoi() to convert to integer.
// For others, use keyword like oct, dec hex etc
switch (fromBase) {
case 1 : cin >> binary; // string binary = "100100101"   
input = stoi(binary, 0, 2);
break;
case 2 : cin >> oct >> input;
break;
case 3 : cin >> input;
break;
case 4 : cin >> hex >> input;
break;
default : cout << "Invalid choice";
break;
}
cout << "Select Output Number Base" << endl;
cout << "1 for conversion to Binary" << endl;
cout << "2 for conversion to Octal" << endl;
cout << "3 for conversion to Decimal" << endl;
cout << "4 for conversion to Hexadecimal" << endl;
cout << "5 for Exit" << endl;
cin >> toBase;
if (5 == toBase) {
return 0;
}
cout << "Output : ";
// For binary use for loop to extract every digit.
// For others, use keyword like oct, dec hex etc
switch (toBase) {
case 1: for (int i = 7; i >= 0; i--) {
cout << ((input >> i) & 1);
}
cout << endl;
break;
case 2: cout << oct << input << endl;
break;
case 3: cout << dec << input << endl;
break;
case 4: cout << hex << input << endl;
break;
default: cout << "Invalid choice";
break;
}
}
  
return 0;
}

Step 2 : Compile the program using g++ or visual studio and run.

Following is my sample output