AoC_2019_Day_3_Part_1a

#! python3

#link https://adventofcode.com/2019/day/3

#TODO: Figure out how to write to .csv instead of .txt!
#! import csv
from time import process_time #i For timing the step calculation process

def clean(wire): #i Split and strip the input to produce a clean list
    wire = wire.split(',')
    for x in range(len(wire)):
        wire[x] = wire[x].strip()
    return wire

#TODO: Figure out how to write to .csv instead of .txt!
def save_list(name, in_list): #i Save to file function
    filename = f'./Day_3/{name}.txt' #i Generate filename
    with open(filename, 'w') as f: #i Context manager
        f.write(str(in_list)) #i Write the list to file as a string

with open('./Day_3/Day_3_Input.txt', 'r') as f: #i Read the input into the two wires and apply the clean() function to them both
    wire1, wire2 = f.readlines()
    wire1, wire2 = [clean(w) for w in [wire1, wire2]]

#print(f'{"-"*30}\nWire 1: {wire1}\nWire 2: {wire2}') #i Print the 'clean' list of instructions for each wire

[save_list(n, s) for n, s in [['wire1_string', wire1], ['wire2_string', wire2]]] #i Save both wire strings to file
print('Both wires saved to file...')

wire1_instructions = [] #i Instantiate empty lists to hold the co-ordinates
wire2_instructions = []

def interpret(wire, instructions_list): #i Split the list items into tuples of direction and distance, inverting any distances in a negative direction
    for instruction in wire:    #i For each instruction in the list of instructions (the wire)
        direction = instruction[0] #i Direction is the letter (R = right, U = up etc.)
        distance = int(instruction[1:]) #i Distance is the value (everything after the letter)

        if direction in ('L', 'D'): #i If the distance is negative (ie Left or Down)
            distance *= -1 #i Invert the number

        instructions_list.append((direction, distance)) #i Append instruction tuples to the approperiate list

[interpret(w, c) for w, c in [[wire1, wire1_instructions], [wire2, wire2_instructions]]] #i Run the interpret() function on both wires, saving the output co-ords to the appropriate lists

#print(f'{"-"*30}\nWire 1 Instructions: {wire1_instructions}\nWire 2 Instructions: {wire2_instructions}') #i Print the lists of co-ordinates

[save_list(n, s) for n, s in [['wire1_instructions', wire1_instructions], ['wire2_instructions', wire2_instructions]]] #i Save both sets of instructions to file
print('Both instruction sets saved...')

wire1_steps = [] #i Instantiate empty lists to hold the steps for each wire
wire2_steps = []

def steps(wire, steps_list): #i Function to calculate and return the steps required to perform each instruction
    if len(steps_list) == 0: #i If the steps_list is empty
        steps_list.append((0,0)) #i Add the first step as the origin
    for instruction in wire: #i For each instruction in the wire (list of instructions)
        if instruction[0] in ('L', 'R'): #i If the direction is on the 'x' axis
            axis = 0 #i Set the axis value to 0
        else: #i If the direction is on the 'y' axis
            axis = 1 #i Set the axis value to 1
        if int(instruction[1]) >= 0: #i If the distance is positive
            iterations = int(instruction[1]) + 1 #i Set the number of iterations to the value of the distance (+1 to account for starting at 0)
        else: #i If the distance is negative
            iterations = (int(instruction[1]) * -1) + 1 #i Set the number of iterations to the value of the distance (inverted to make positive) (+1 to account for starting at 0)
        for i in range(1, iterations): #i For each of the determined iterations (distance of the instruction)
            prev_step = steps_list[len(steps_list)-1] #i The previous step is the last one in the list
            this_step = list(prev_step) #i This step is initially a copy of the previous step
            if int(instruction[1]) == 0: #! If the distance is zero - probably not needed as zero distance = 0 iterations, which would be skipped
                this_step[axis] += 0 #! Don't change anything
            elif int(instruction[1]) > 0: #i If the distance is positive
                this_step[axis] += 1 #i Increment the relevant axis by 1
            else: #i If the distance is positive
                this_step[axis] -= 1 #i Reduce the relevant axis by 1
            steps_list.append(tuple(this_step)) #i Add this step into the list of steps

print('Starting timer...')

t1_start = process_time() #i Start timing the step calulation process

[steps(c, s) for c, s in [[wire1_instructions, wire1_steps], [wire2_instructions, wire2_steps]]] #i Run the steps() function on each of the co-ordinate lists, saving the output to the appropriate steps lists

t1_stop = process_time() #i Stop timing the step calculation process

#print(f'{"-"*30}\nWire 1 Steps: {wire1_steps}\nWire 2 Steps: {wire2_steps}') #i Print the lists of steps for each wire

elapsed_time = t1_stop - t1_start #i Calculate the elapsed time

print(f'Time taken to compute both strings (total length {len(wire1_steps) + len(wire2_steps)}) was {elapsed_time}') #i Print the combined length and elapsed time

[save_list(n, s) for n, s in [['wire1_steps', wire1_steps], ['wire2_steps', wire2_steps]]] #i Save both sets of calculated steps to file
print('Both step files saved...')

print('Program completed.') #i Notify user of program completion