Sorting a Stack using Recursion.py

def sortedInsert(s , element): 

      

    # Base case: Either stack is empty or newly inserted 

    # item is greater than top (more than all existing) 

    if len(s) == 0 or element > s[-1]: 

        s.append(element) 

        return

    else: 

          

        # Remove the top item and recur 

        temp = s.pop() 

        sortedInsert(s, element) 

  

        # Put back the top item removed earlier 

        s.append(temp) 

  
# Method to sort stack 

def sortStack(s): 

      

    # If stack is not empty 

    if len(s) != 0: 

          

        # Remove the top item 

        temp = s.pop() 

          

        # Sort remaining stack 

        sortStack(s) 

          

        # Push the top item back in sorted stack 

        sortedInsert(s , temp) 

  
# Printing contents of stack 

def printStack(s): 

    for i in s[::-1]: 

            print(i , end=" ") 

    print() 

      

if __name__=='__main__': 

    s = [ ] 

    s.append(30) 

    s.append(-5) 

    s.append(18) 

    s.append(14) 

    s.append(-3) 

  

    print("Stack elements before sorting: ") 

    printStack(s) 

  

    sortStack(s) 

  

    print("\nStack elements after sorting: ") 

    printStack(s)