import 2019 aoc

2019/day5/day5.py

@@ -0,0 +1,163 @@
+#! /usr/bin/env python3
+from collections import namedtuple
+from enum import Enum
+import logging
+
+logging.basicConfig(format="%(levelname)s:%(message)s", level=logging.WARN)
+
+
+def get_nth_digit(n, number):
+    "Returns the nth digit of the input number"
+    return number // 10 ** n % 10
+
+
+class Operation(Enum):
+    ADDITION = 1
+    MULTIPLICATION = 2
+    INPUT = 3
+    OUTPUT = 4
+    JMP_IF_TRUE = 5
+    JMP_IF_FALSE = 6
+    LESS_THAN = 7
+    EQUALS = 8
+    TERMINATION = 99
+
+
+class Mode(Enum):
+    POSITION = 0
+    IMMEDIATE = 1
+
+
+class Instruction:
+    def __init__(self, opcode):
+        self.operation = Operation(opcode % 100)
+        self.modes = [Mode(get_nth_digit(n, opcode)) for n in range(2, 5)]
+        self.handler_name = f"handle_{self.operation.name.lower()}"
+        self.handler = getattr(self, self.handler_name, self.handle_termination)
+
+    def __repr__(self):
+        return f"Instruction({self.operation}, {self.modes})"
+
+    def handle(self, program, ip):
+        return self.handler(program, ip)
+
+    def handle_addition(self, program, ip):
+        first, second = self._get_parameters(program, ip)
+        logging.debug(f"ADD {first} {second}")
+        result = first + second
+        # the last mode should *always* be POSITION
+        program[program[ip + 3]] = result
+        ip += 4
+        return ip
+
+    def handle_multiplication(self, program, ip):
+        first, second = self._get_parameters(program, ip)
+        logging.debug(f"MUL {first} {second}")
+        result = first * second
+        # the last mode should *always* be POSITION
+        program[program[ip + 3]] = result
+        ip += 4
+        return ip
+
+    def handle_input(self, program, ip):
+        ip += 2
+        program[program[ip + 1]] = int(input("Enter ID > "))
+        return ip
+
+    def handle_output(self, program, ip):
+        print("OUT ", program[program[ip + 1]])
+        ip += 2
+        return ip
+
+    def handle_jmp_if_true(self, program, ip):
+        first, second = self._get_parameters(program, ip)
+        logging.debug(f"JMPT {first} {second}")
+        return second if first != 0 else ip + 3
+
+    def handle_jmp_if_false(self, program, ip):
+        first, second = self._get_parameters(program, ip)
+        logging.debug(f"JMPF {first} {second}")
+        return second if first == 0 else ip + 3
+
+    def handle_less_than(self, program, ip):
+        first, second = self._get_parameters(program, ip)
+        logging.debug(f"LT {first} {second}")
+        program[program[ip + 3]] = int(first < second)
+        ip += 4
+        return ip
+
+    def handle_equals(self, program, ip):
+        first, second = self._get_parameters(program, ip)
+        logging.debug(f"EQ {first} {second}")
+        program[program[ip + 3]] = int(first == second)
+        ip += 4
+        return ip
+
+    def handle_termination(self, program, ip):
+        print("HALT")
+        return ip
+
+    def _get_parameters(self, program, ip):
+        first = (
+            program[ip + 1]
+            if self.modes[0] is Mode.IMMEDIATE
+            else program[program[ip + 1]]
+        )
+        second = (
+            program[ip + 2]
+            if self.modes[1] is Mode.IMMEDIATE
+            else program[program[ip + 2]]
+        )
+        return first, second
+
+
+def interpret_intcode(program, stdin=None):
+    ip = 0
+    while program[ip] != 99:
+        opcode = program[ip]
+        instruction = Instruction(opcode)
+        ip = instruction.handle(program, ip)
+
+
+def tests():
+    inputs = (
+        [1, 0, 0, 0, 99],  # ADD 1 + 1 to location 0
+        [2, 3, 0, 3, 99],  # MUL 2 * 3 to location 3
+        [2, 4, 4, 5, 99, 0],
+        [1, 1, 1, 4, 99, 5, 6, 0, 99],
+        [1101, 1, 1, 0, 99],  # ADD 1 + 1 to location 0 (direct access)
+    )
+    expected_outputs = (
+        [2, 0, 0, 0, 99],  # 1 + 1 = 2
+        [2, 3, 0, 6, 99],  # 3 * 2 = 6
+        [2, 4, 4, 5, 99, 9801],  # 99 * 99 = 9801
+        [30, 1, 1, 4, 2, 5, 6, 0, 99],
+        [2, 1, 1, 0, 99],  # 1 + 1 = 2 (direct access)
+    )
+    for i, inp in enumerate(inputs):
+        result = inp[:]
+        interpret_intcode(result)
+        assert (
+            result == expected_outputs[i]
+        ), f"Expected output for {inp} is {expected_outputs[i]}, but found {result} instead."
+    print("\nAll tests passed.\n")
+
+
+def run_input_program(filename):
+    import os
+
+    SCRIPT_DIR = os.path.dirname(os.path.realpath(__file__))
+    with open(os.path.join(SCRIPT_DIR, filename)) as inp:
+        print("Start of input program.")
+        memory = [int(x) for x in inp.readline().strip().split(",")]
+        interpret_intcode(memory, 5)
+
+
+if __name__ == "__main__":
+    tests()
+    # a = [3, 12, 6, 12, 15, 1, 13, 14, 13, 4, 13, 99, -1, 0, 1, 9]
+    # b = [3, 3, 1105, -1, 9, 1101, 0, 0, 12, 4, 12, 99, 1]
+
+    # interpret_intcode(b, 0)
+    # interpret_intcode(a, 0)
+    run_input_program("input.txt")