L14Q3_NumbersInLists.py

# Numbers in lists by SeanMc from forums
# define a procedure that takes in a string of numbers from 1-9 and
# outputs a list with the following parameters:
# Every number in the string should be inserted into the list.
# If a number x in the string is less than or equal
# to the preceding number y, the number x should be inserted
# into a sublist. Continue adding the following numbers to the
# sublist until reaching a number z that
# is greater than the number y.
# Then add this number z to the normal list and continue.

#Hint - "int()" turns a string's element into a number

def numbers_in_lists(string):
    output = [int(string[0])]
    i = 1
    for i in range(1,len(string)):
        counter = int(string[i])
        #print 'iterating...i:',i,'output[-1]:',output[-1],type(output[-1]),'counter:',counter
        if type(output[-1]) == int:
            if counter > output[-1]:
                output.append(counter)
                continue
            if counter <= output[-1]:
                output.append([counter])
                continue
        if type(output[-1]) == list:
            if counter > output[-2]:
                output.append(counter)
                continue
            else:
                output[-1] = output[-1] + [counter]
                continue
    return output

#testcases
string = '543987'
result = [5,[4,3],9,[8,7]]
print repr(string), numbers_in_lists(string) == result

string= '987654321'
result = [9,[8,7,6,5,4,3,2,1]]
print repr(string), numbers_in_lists(string) == result

string = '455532123266'
result = [4, 5, [5, 5, 3, 2, 1, 2, 3, 2], 6, [6]]
print repr(string), numbers_in_lists(string) == result

string = '123456789'
result = [1, 2, 3, 4, 5, 6, 7, 8, 9]
print repr(string), numbers_in_lists(string) == result