Advent of Code 2019: Day 13
Continuing with the computer, now I’m using it to power an arcade game. I’ll use the given intcodes to run the game, and I’m responsible for moving the joystick via input to the game. This challenge was awesome. I made a video of the game running in my terminal, which wasn’t necessary, but turned out pretty good.
Challenge
The puzzle can be found here. I need to write the code for an aracade game that is a take on the classic game Breakout. The program will draw the blocks on the screen. In part 1, it just paints a board, and I need to count the number of blocks. For part two, I change the input into game mode, and then I’m also responsible for moving the joystick and trying to keep the ball alive.
Part 1
Part 1 was really easy. I’ve already got the Computer. I just need to create a Computer object using the program input and then run it until it finishing, counting the number of times it returns a block type (every 3rd output) of 2.
comp = Computer(program_str)
count = 0
while not comp.done:
_, _, block = comp.compute(None), comp.compute(None), comp.compute(None)
if block == 2:
count += 1
print(f'Part 1: {count}')
That runs and returns the answer:
$ time ./day13.py 13-puzzle_input.txt
Part 1: 251
real 0m0.066s
user 0m0.059s
sys 0m0.004s
Part 2
Now I need to wrap the arcade game around this computer. I started to create a Breakout class, but then realized that I’d be doing the entire game in the __init__ function. I created a
program_str = '2' + program_str[1:]
comp = Computer(program_str)
screen = defaultdict(int)
joystick = 0
score = 0
while not comp.done:
x = comp.compute(joystick)
y = comp.compute(joystick)
b = comp.compute(joystick)
if (x, y) == (-1, 0):
score = b
else:
screen[(x,y)] = b
Now I wanted to see the screen, so I created a print_screen function as well:
def print_screen(screen, score):
icons = {0: ' ', 1: chr(9608), 2: '.', 3: '_', 4: 'o'}
for y in range(20):
output = ''
for x in range(37):
output += icons[screen[(x,y)]]
print(output)
print(f' {"-"*16}{score:05d}{"-"*16}')
I’ll add a call at the end of each loop. The ranges or 30x37 comes from playing with it a few times to get the dimensions correct.
The first print looks like:
█
--000000--
Then a few more:
█████
--000000--
It’s building the top across the board. I’ll skip forward a bunch, and can see the board built, with walls and blocks, and then the ball is added:
█████████████████████████████████████
█ █
█ .. .. .......... . .. . ... █
█ ... .. ............ . ...... . █
█ .... . .. ... ... .. . . . . █
█ .... ...... ....... .. ... ... █
█ ........ . .. ... .. ... . . █
█ .. . .. .. .. ........ ... .. █
█ ... .... .. .... . ........ . █
█ .... ... .. .. ... .. .. .. █
█ . . .. . . .. ... ... . .. █
█ ..... . .. ... ... .. ... .. █
█ .... . .... ... . .. . ... █
█ .. ... . .... . .. . .... █
█ █
█ o
--000000--
A bunch more cycles and I get the paddle:
█████████████████████████████████████
█ █
█ .. .. .......... . .. . ... █
█ ... .. ............ . ...... . █
█ .... . .. ... ... .. . . . . █
█ .... ...... ....... .. ... ... █
█ ........ . .. ... .. ... . . █
█ .. . .. .. .. ........ ... .. █
█ ... .... .. .... . ........ . █
█ .... ... .. .. ... .. .. .. █
█ . . .. . . .. ... ... . .. █
█ ..... . .. ... ... .. ... .. █
█ .... . .... ... . .. . ... █
█ .. ... . .... . .. . .... █
█ █
█ o █
█ █
█ █
█ _ █
█ █
--000000--
Then the ball starts moving diagonally down to the right and bounces off the paddle:
█████████████████████████████████████
█ █
█ .. .. .......... . .. . ... █
█ ... .. ............ . ...... . █
█ .... . .. ... ... .. . . . . █
█ .... ...... ....... .. ... ... █
█ ........ . .. ... .. ... . . █
█ .. . .. .. .. ........ ... .. █
█ ... .... .. .... . ........ . █
█ .... ... .. .. ... .. .. .. █
█ . . .. . . .. ... ... . .. █
█ ..... . .. ... ... .. ... .. █
█ .... . .... ... . .. . ... █
█ .. ... . .... . .. . .... █
█ █
█ █
█ o █
█ █
█ _ █
█ █
--000000--
█████████████████████████████████████
█ █
█ .. .. .......... . .. . ... █
█ ... .. ............ . ...... . █
█ .... . .. ... ... .. . . . . █
█ .... ...... ....... .. ... ... █
█ ........ . .. ... .. ... . . █
█ .. . .. .. .. ........ ... .. █
█ ... .... .. .... . ........ . █
█ .... ... .. .. ... .. .. .. █
█ . . .. . . .. ... ... . .. █
█ ..... . .. ... ... .. ... .. █
█ .... . .... ... . .. . ... █
█ .. ... . .... . .. . .... █
█ █
█ █
█ █
█ o █
█ _ █
█ █
--000000--
█████████████████████████████████████
█ █
█ .. .. .......... . .. . ... █
█ ... .. ............ . ...... . █
█ .... . .. ... ... .. . . . . █
█ .... ...... ....... .. ... ... █
█ ........ . .. ... .. ... . . █
█ .. . .. .. .. ........ ... .. █
█ ... .... .. .... . ........ . █
█ .... ... .. .. ... .. .. .. █
█ . . .. . . .. ... ... . .. █
█ ..... . .. ... ... .. ... .. █
█ .... . .... ... . .. . ... █
█ .. ... . .... . .. . .... █
█ █
█ █
█ o █
█ █
█ _ █
█ █
--000000--
█████████████████████████████████████
█ █
█ .. .. .......... . .. . ... █
█ ... .. ............ . ...... . █
█ .... . .. ... ... .. . . . . █
█ .... ...... ....... .. ... ... █
█ ........ . .. ... .. ... . . █
█ .. . .. .. .. ........ ... .. █
█ ... .... .. .... . ........ . █
█ .... ... .. .. ... .. .. .. █
█ . . .. . . .. ... ... . .. █
█ ..... . .. ... ... .. ... .. █
█ .... . .... ... . .. . ... █
█ .. ... . .... . .. . .... █
█ █
█ o █
█ █
█ █
█ _ █
█ █
--000000--
I’ll need to add code to watch the ball and set the joystick. I’ll find them using a list comprehension:
ball = [p for p in screen if screen[p] == 4]
paddle = [p for p in screen if screen[p] == 3]
Each of those should return [] before the item is added to the screen or if it’s taken off because it’s been moved, and [(x,y)] otherwise.
Now I’ll just tilt my joystick to follow the ball:
if ball and paddle:
if ball[0][0] < paddle[0][0]:
joystick = -1
elif ball[0][0] > paddle[0][0]:
joystick = 1
else:
joystick = 0
At this point I have all I need to run to completion and print the score:
$ time ./day13.py 13-puzzle_input.txt
Part 1: 251
Part 2: 12779
real 0m2.627s
user 0m2.623s
sys 0m0.004s
But I wanted to add the graphic part to this. I’ll add a variable need_to_print, set to False at the start of each loop. If the score or the ball position changes, I’ll set it to true. I’ll print the graphic version if sys.argv[2] == watch. I’ll also print the code to clear the terminal before each print, so it looks like a video. It looks pretty good for terminal output:
Final Code
#!/usr/bin/env python3
import sys
import time
from collections import defaultdict
class Computer:
def __init__(self, program):
self.program = defaultdict(int)
for i, v in enumerate(list(map(int, program.split(",")))):
self.program[i] = v
self.done = False
self.eip = 0
self.rel_base = 0
def get_param(self, mode, reg):
value = self.program[self.eip + reg]
if mode == "0":
return self.program[value]
elif mode == "1":
return value
elif mode == "2":
return self.program[self.rel_base + value]
else:
print("Error: Invalid Parameter Mode")
sys.exit()
def get_address(self, mode, reg):
value = self.program[self.eip + reg]
if mode == "0":
return value
elif mode == "2":
return self.rel_base + value
else:
print("Error: Invalid Address Mode")
sys.exit()
def compute(self, signal):
while True:
inst = self.program[self.eip]
op = inst % 100
mode3, mode2, mode1 = f"{inst // 100:03d}"
if op == 1:
self.program[self.get_address(mode3, 3)] = self.get_param(
mode1, 1
) + self.get_param(mode2, 2)
self.eip += 4
elif op == 2:
self.program[self.get_address(mode3, 3)] = self.get_param(
mode1, 1
) * self.get_param(mode2, 2)
self.eip += 4
elif op == 3:
self.program[self.get_address(mode1, 1)] = signal
self.eip += 2
elif op == 4:
self.eip += 2
return self.get_param(mode1, 1 - 2)
elif op == 5:
if self.get_param(mode1, 1) != 0:
self.eip = self.get_param(mode2, 2)
else:
self.eip += 3
elif op == 6:
if self.get_param(mode1, 1) == 0:
self.eip = self.get_param(mode2, 2)
else:
self.eip += 3
elif op == 7:
self.program[self.get_address(mode3, 3)] = int(
self.get_param(mode1, 1) < self.get_param(mode2, 2)
)
self.eip += 4
elif op == 8:
self.program[self.get_address(mode3, 3)] = int(
self.get_param(mode1, 1) == self.get_param(mode2, 2)
)
self.eip += 4
elif op == 9:
self.rel_base += self.get_param(mode1, 1)
self.eip += 2
elif op == 99:
self.done = True
return 0
else:
print("Error")
sys.exit()
def print_screen(screen, score):
print("\33[2J")
icons = {0: " ", 1: chr(9608), 2: ".", 3: "_", 4: "o"}
for y in range(20):
output = " "
for x in range(37):
output += icons[screen[(x, y)]]
print(output)
print(f' {"-"*16}{score:05d}{"-"*16}')
with open(sys.argv[1], "r") as f:
program_str = f.read().strip()
comp = Computer(program_str)
count = 0
while not comp.done:
_, _, block = comp.compute(None), comp.compute(None), comp.compute(None)
if block == 2:
count += 1
watch = int(len(sys.argv) > 2 and sys.argv[2] == "watch")
program_str = "2" + program_str[1:]
comp = Computer(program_str)
screen = defaultdict(int)
joystick = 0
score = 0
while not comp.done:
need_to_print = False
x = comp.compute(joystick)
y = comp.compute(joystick)
b = comp.compute(joystick)
if (x, y) == (-1, 0):
score = b
need_to_print = True
else:
screen[(x, y)] = b
if b == 4:
need_to_print = True
ball = [p for p in screen if screen[p] == 4]
paddle = [p for p in screen if screen[p] == 3]
if ball and paddle:
if ball[0][0] < paddle[0][0]:
joystick = -1
elif ball[0][0] > paddle[0][0]:
joystick = 1
else:
joystick = 0
if watch and need_to_print:
print_screen(screen, score)
time.sleep(0.05)
print(f"Part 1: {count}")
print(f"Part 2: {score}")