"""
Write a program that reads the string and replaces '*' with 'a'. 
Pay attention: you need to create a new string. 
"""
def replace_char(str, old_char, new_char):
	#replaces old_char with new_char and returns a new string
	#you cannot change the string
	#you have to create a new string

	new_str=""        
	for item in str:
		if(item==old_char):
			new_str+=new_char
		else:
			new_str+=item
	return new_str


def main():
	#solution 1
	print('solution 1')
	str=input("enter string ")
	new_str=""
	size=len(str)
	for i in range(size):
		if(str[i]=='*'):
			new_str=new_str+'a'
		else:
			new_str=new_str+str[i]
	print("new string",new_str)

	#solution 2
	print('solution 2')
	str=input("enter string ")
	new_str=""
	for item in str:
		if(item=='*'):
			new_str=new_str+'a'
		else:
			new_str=new_str+item
	print("new string",new_str)
	#solution 3
	print('solution 3')
	str=input("enter string ")
	print("new string",replace_char(str,'*','a'))
main()