vhs_problem.py

def return_max_record(timetable):
    '''This function returns the maximum number of possible non-concurrent
    recordings from VHS. Input a list with each row formatted: 
    [start time, end time]'''

    for times in timetable:
        times.append(times[1] - times[0])

    # Maximizing the number 
    timetable = sorted(timetable, key = lambda x: x[2])
    
    recorded_timetable = []
    recorded_timetable.append(timetable[0])
    
    for show in timetable:
        # Fringe cases
        # Checking beginning
        if show[1] <= recorded_timetable[0][0]:
            recorded_timetable.insert(0, show)
        # Checking end
        elif show[0] >= recorded_timetable[len(recorded_timetable) - 1][1]:
            recorded_timetable.append(show)
        # Seeing if elements fit in "between" any of the shows we've recorded
        else:
            for i in range(1, len(recorded_timetable) - 2):
                if show[1] >= recorded_timetable[i][0] and show[0] <= \
                recorded_timetable[i + 1][1]:
                    recorded_timetable.insert(i + 1, show)
    return len(recorded_timetable)
    
    
challenge_input = ""
input_table = []
        
filename = input("Enter filename of input: ")
with open(filename, "r") as f:
    for line in f:
        temp_tuple = line.split()
        input_table.append([int(temp_tuple[0]), int(temp_tuple[1])]) 
print(return_max_record(input_table))