#SUMMER OF '69: Return the sum of the numbers in the array, 
#except ignore sections of numbers starting with a 6 and extending to the next 9 
#(every 6 will be followed by at least one 9). 
#Return 0 for no numbers.
#summer_69([1, 3, 5]) --> 9
#summer_69([4, 5, 6, 7, 8, 9]) --> 9
#summer_69([2, 1, 6, 9, 11]) --> 14
def summ(a):
    total = 0
    add = True
    for num in a:
        while add:
            if num != 6:
                total +=num
                break
            else:
                add=False
        while not add:
            if num !=9:
                break
            else:
                add= True 
                break
    print (total)
summ([21,3,5])
