alternating.py

def is_alternating(arr):
    if len(arr)<3:
        return True
    even=arr[0]
    for i in range(2,len(arr),2):
        if arr[i]!=even:
            return False
    odd=arr[1]
    for i in range(1,len(arr),2):
        if arr[i]!=odd:
            return False
    return True

def main():
    print("alternating.py\nDeveloped by Pedro Izecksohn.")
    s=input("Enter the values separated by comma: ")
    arr=s.split(",")
    print(is_alternating(arr))

if __name__=="__main__":
    main()