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C++ Exercises: Convert a binary number to decimal number

C++ For Loop: Exercise-73 with Solution

Write a program in C++ to convert a binary number to decimal number.

Pictorial Presentation:

C++ Exercises: Convert a binary number to decimal number

Sample Solution:-

C++ Code :

#include <iostream>
#include <math.h>
using namespace std;
 
int main()
{
  long binaryNumber, decimalNumber = 0, j = 1, remainder;
	cout << "\n\n Convert a  binary number to decimal number:\n";
	cout << "-----------------------------------------------\n";
	cout << " Input a binary number: ";
	cin>> binaryNumber;
  while (binaryNumber != 0) 
  {
   remainder = binaryNumber % 10;
   decimalNumber = decimalNumber + remainder * j;
   j = j * 2;
   binaryNumber = binaryNumber / 10;
  }
  cout<<" The decimal number: " << decimalNumber<<"\n";
} 

Sample Output:

Convert a  binary number to decimal number:                           
-----------------------------------------------                        
 Input a binary number: 1011                                           
 The decimal number: 11

Flowchart:

Flowchart: Convert a binary number to decimal number

C++ Code Editor:

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Previous: Write a program in C++ to convert a decimal number to octal number.
Next: Write a program in C++ to convert a binary number to hexadecimal number.

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C++ Programming: Tips of the Day

What is a smart pointer and when should I use one?

This answer is rather old, and so describes what was 'good' at the time, which was smart pointers provided by the Boost library. Since C++11, the standard library has provided sufficient smart pointers types, and so you should favour the use of std::unique_ptr, std::shared_ptr and std::weak_ptr.

There was also std::auto_ptr. It was very much like a scoped pointer, except that it also had the "special" dangerous ability to be copied - which also unexpectedly transfers ownership.

It was deprecated in C++11 and removed in C++17, so you shouldn't use it.

std::auto_ptr<MyObject> p1 (new MyObject());
std::auto_ptr<MyObject> p2 = p1; // Copy and transfer ownership. 
                                 // p1 gets set to empty!
p2->DoSomething(); // Works.
p1->DoSomething(); // Oh oh. Hopefully raises some NULL pointer exception.

Ref : https://bit.ly/3mc9GHE