# Advent of Code Day 21¶

## Intcode¶

In [1]:
def readfile(path):
with open(path) as input_file:

def params(program, i, count):
modes = str(program[i] // 100)[::-1]
result = []

for x in range(count - 1):
arg = program[i + 1 + x]
if x >= len(modes) or modes[x] == "0":
result.append(program[arg])
elif modes[x] == "2":
result.append(program[program.offset + arg])
else:
result.append(arg)

output = program[i + count]
if len(modes) >= count and modes[count - 1] == "2":
output += program.offset

result.append(output) # output
return result

def add(program, i, **kwargs):
assert program[i] % 100 == 1
a, b, out = params(program, i, 3)
program[out] = a + b
return i + 4, None

def mul(program, i, **kwargs):
assert program[i] % 100 == 2
a, b, out = params(program, i, 3)
program[out] = a * b
return i + 4, None

def inp(program, i, input_value, **kwargs):
assert program[i] % 100 == 3
out, = params(program, i, 1)
program[out] = input_value
# print(f"> {program[i]} program[{out}] = {program[out]}")
return i + 2, None

def out(program, i, **kwargs):
assert program[i] % 100 == 4
val, _ = params(program, i, 2)
# print(f"> {val}")
return i + 2, val

def jit(program, i, **kwargs):
assert program[i] % 100 == 5
test, ip, _ = params(program, i, 3)
if test != 0:
return ip, None
return i + 3, None

def jif(program, i, **kwargs):
assert program[i] % 100 == 6
test, ip, _ = params(program, i, 3)
if test == 0:
return ip, None
return i + 3, None

def lt(program, i, **kwargs):
assert program[i] % 100 == 7
a, b, out = params(program, i, 3)
program[out] = int(a < b)
return i + 4, None

def eq(program, i, **kwargs):
assert program[i] % 100 == 8
a, b, out = params(program, i, 3)
program[out] = int(a == b)
return i + 4, None

def rbo(program, i, **kwargs):
assert program[i] % 100 == 9
delta, _ = params(program, i, 2)
program.offset += delta
# print (f"> rbo = {program.offset}" )
return i + 2, None

operations = { 1: add, 2: mul, 3: inp, 4: out, 5: jit, 6: jif, 7: lt, 8: eq, 9: rbo }

class Program(list):
def __init__(self, *args, **kwargs):
super(Program, self).__init__(args[0])
self.offset = 0

def compute(program, debug=False):
program = Program(program)

l = len(program)
i = 0
output_value = None
last_output = None

while i < l:
op = program[i]
if op == 99:
if debug:
print(f">> exit {output_value}")
return

if debug:
print(f">> {i}, {list(enumerate(program))[i:i+5]}")

if op % 100 == 3:
input_value = yield
else:
input_value = None

i, output_value = operations[op % 100](program, i, input_value=input_value)

if output_value is not None:
yield output_value

raise Exception("Didn't terminate properly")

def process(listing):
lst = list(map(int, listing.split(",")))
lst.extend([0] * 100000)
return lst

In [3]:
input21 = readfile("AoC/input21.txt")

In [40]:
def out(program):
while (output := next(program)):
if output < 128:
print(chr(output), end="")
else:
print(output, end="")

def inp(program, text):
result = None
for ch in text:
result = program.send(ord(ch))
if result:
print(chr(result), end="")
return result

def jumper(input21):
program = compute(process(input21))
out(program)

inp(program, "NOT A J\n") # J = A is a hole
inp(program, "NOT B T\n") # T = B is a hole
inp(program, "OR T J\n")  # J = A OR B is a hole
inp(program, "NOT C T\n") # T = C is a hole
inp(program, "OR J T\n")  # T = A or B or C is a hole

inp(program, "AND D T\n") # T = (A or B or C is a hole) AND D is not.

inp(program, "NOT T J\n") # J = !T
inp(program, "NOT J J\n") # J = !J = !!T

inp(program, "WALK\n")

out(program)

def jumper2(input21):
program = compute(process(input21))
out(program)

# Jump if there is ground at 4, repeated twice

inp(program, "NOT A J\n") # J = A is a hole
inp(program, "NOT B T\n") # T = B is a hole
inp(program, "OR T J\n")  # J = A OR B is a hole
inp(program, "NOT C T\n") # T = C is a hole
inp(program, "OR J T\n")  # T = A or B or C is a hole

inp(program, "AND D T\n") # T = (A or B or C is a hole) AND D is not.

inp(program, "NOT I J\n") # J = !I
inp(program, "NOT J J\n") # J = I # Can jump from E

inp(program, "OR F J\n") # J = I OR F # Can move forward twice

inp(program, "AND E J\n") # J = E && (F || I) # Can move to E

inp(program, "OR H J\n") # J = H || (E && (F || I))

inp(program, "AND T J\n") # J = !T
inp(program, "RUN\n")

out(program)

In [41]:
jumper(input21)

Input instructions:

Walking...

19359316

StopIterationTraceback (most recent call last)
<ipython-input-41-a06bdcb033c8> in <module>
----> 1 jumper(input21)

<ipython-input-40-f55dbcfc39c5> in jumper(input21)
31     inp(program, "WALK\n")
32
---> 33     out(program)
34
35

<ipython-input-40-f55dbcfc39c5> in out(program)
1 def out(program):
----> 2     while (output := next(program)):
3         if output < 128:
4             print(chr(output), end="")
5         else:

StopIteration: 
In [42]:
jumper2(input21)

Input instructions:

Running...

1141281622

StopIterationTraceback (most recent call last)
<ipython-input-42-20a5bbd1ec50> in <module>
----> 1 jumper2(input21)

<ipython-input-40-f55dbcfc39c5> in jumper2(input21)
61     inp(program, "RUN\n")
62
---> 63     out(program)
64

<ipython-input-40-f55dbcfc39c5> in out(program)
1 def out(program):
----> 2     while (output := next(program)):
3         if output < 128:
4             print(chr(output), end="")
5         else:

StopIteration: 
In [ ]: