HackEx Ad Time

# Output - How many days it would take to get to X days left.
# Input - Total time left.

def checkInput(input):
    # Input is type string.

    for char in input:
        #print("Character:", input[char], "Index:", char)
        if not char in "0123456789.":
             return False
    return True

def adWatch(totalTime, time):
    reducedTime = totalTime
    print("Starting time:", totalTime)
    reducedTime *= 0.9
    print("-10%", reducedTime, "(-%f)" % (totalTime - reducedTime))
    tempTime = reducedTime
    reducedTime *= 0.92
    print("-08%", reducedTime, "(-%f)" % (tempTime - reducedTime))
    tempTime = reducedTime
    reducedTime *= 0.94
    print("-06%", reducedTime, "(-%f)" % (tempTime - reducedTime))
    tempTime = reducedTime
    reducedTime *= 0.96
    print("-04%", reducedTime, "(-%f)" % (tempTime - reducedTime))
    tempTime = reducedTime
    reducedTime *= 0.98
    print("-02%", reducedTime, "(-%f)" % (tempTime - reducedTime))
    tempTime = reducedTime
    reducedTime *= 0.99
    print("-01%", reducedTime, "(-%f)" % (tempTime - reducedTime))
    tempTime = reducedTime

    # Even though the percentages add up to 31%, it actually only subtracts 27.507898% off the original time.
    print("Time reduced by %f" % (totalTime - reducedTime) + " (-%f" % (100 / (time / (time - reducedTime))) + "%)")
    return reducedTime


def main():
    time = input("How long will the process take? (days): ")

    if checkInput(time) == False:
        print("Invalid input.")
        return
    else: time = float(time)

    print()

    count = 1
    newTime = time
    while newTime > 1:
        print("Day %d:" % (count))
        newTime = adWatch(newTime, time) - 1
        count += 1
        print()

    print("Day %d:" % (count))
    print(newTime)

main()