Reverse.string.python

# Python program to reverse a string using stack 
  
# Function to create an empty stack.  
# It initializes size of stack as 0 
def createStack(): 
    stack=[] 
    return stack 
  
# Function to determine the size of the stack 
def size(stack): 
    return len(stack) 
  
# Stack is empty if the size is 0 
def isEmpty(stack): 
    if size(stack) == 0: 
        return true 
  
# Function to add an item to stack .  
# It increases size by 1  
def push(stack,item): 
    stack.append(item) 
  
#Function to remove an item from stack.  
# It decreases size by 1 
def pop(stack): 
    if isEmpty(stack): return
    return stack.pop() 
  
# A stack based function to reverse a string 
def reverse(string): 
    n = len(string) 
      
    # Create a empty stack 
    stack = createStack() 
  
    # Push all characters of string to stack 
    for i in range(0,n,1): 
        push(stack,string[i]) 
  
    # Making the string empty since all  
    #characters are saved in stack  
    string="" 
  
    # Pop all characters of string and  
    # put them back to string 
    for i in range(0,n,1): 
        string+=pop(stack) 
          
    return string 
      
# Driver program to test above functions 
string="GeeksQuiz"
string = reverse(string) 
print("Reversed string is " + string)