Generate Binary Numbers

Statement

Given a number N. The task is to generate and print all binary numbers with decimal values from 1 to N.

Pseudo code

1. Create an empty queue of strings
2. Enqueue the first binary number “1” to queue.
3. Now run a loop for generating and printing n binary numbers.
   • Dequeue and store the front of queue in a list.
   • Append “0” at the end of front item and enqueue it.
   • Append “1” at the end of front item and enqueue it.
4. Return the list containing the binary numbers.

Code

vector<string> generatePrintBinary(int n)
{
    // Create queue and answer vector
    queue<string> q;
    vector<string> ans;

    // Initially push one in the queue
    q.push("1");

    // while n is not 0 run the loop
    while (n--)
    {
        // store front in temp and pop front
        string temp = q.front();
        q.pop();
        
        // push into the vector
        ans.push_back(temp);

        // first push temp with 0 then with 1
        q.push(temp+'0');
        q.push(temp+'1');
    }
    return ans;
}

References

• GFG: link