Day 7

2019/day7.py

@@ -0,0 +1,22 @@
+import itertools
+
+from intcode import Intcode
+
+
+def main():
+    with open("day7.txt", "rt") as input_file:
+        first_line = input_file.readlines()[0]
+    codes = Intcode.parse_input(first_line)
+
+    phase_settings_perm = itertools.permutations(range(5), 5)
+    max_output = 0
+    for phases in phase_settings_perm:
+        inout = 0
+        for amp_id in range(5):
+            inout = Intcode(codes).run([phases[amp_id], inout])
+        max_output = max(max_output, inout)
+    print("Max output:", max_output)
+
+
+if __name__ == "__main__":
+    main()

2019/intcode.py

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+""" Intcode refactored from day 7. """
+
+from enum import IntEnum
+import sys
+
+
+class Op(IntEnum):
+    ADD = 1
+    MUL = 2
+    IN = 3
+    OUT = 4
+    JNZ = 5
+    JEZ = 6
+    LT = 7
+    EQ = 8
+    HALT = 99
+
+
+class PMode(IntEnum):
+    POS = 0
+    IMM = 1
+
+
+class Intcode(object):
+
+    def __init__(self, program, print_output=False):
+        self.memory = program.copy()
+        self.ip = 0
+        self.inputs = []
+        self.ctx_op = None
+        self.ctx_modes = None
+        self.halt = False
+        self.outputs = []
+        self.print_output = print_output
+
+    @staticmethod
+    def parse_input(text):
+        return [int(i) for i in text.rstrip().split(",")]
+    
+    def run(self, inputs):
+        self.inputs = inputs
+        handlers = self.get_handlers()
+        while not self.halt:
+            self.read_code()
+            handler = handlers.get(self.ctx_op)
+            if not handler:
+                sys.exit("Wrong opcode: {}".format(self.ctx_op))
+            handler()
+        return self.outputs[-1]
+
+    def get_handlers(self):
+        return {
+            Op.ADD: self.op_add,
+            Op.MUL: self.op_mul,
+            Op.IN: self.op_in,
+            Op.OUT: self.op_out,
+            Op.JNZ: self.op_jnz,
+            Op.JEZ: self.op_jez,
+            Op.LT: self.op_lt,
+            Op.EQ: self.op_eq,
+            Op.HALT: self.op_halt,
+        }
+
+    def read_code(self):
+        code = self.memory[self.ip]
+        self.ctx_op = code % 100
+        code //= 100
+        self.ctx_modes = []
+        for _ in range(0, 3):
+            self.ctx_modes.append(PMode(code % 10))
+            code //= 10
+
+    def param(self, index):
+        mode = self.ctx_modes[index - 1]
+        if mode == PMode.POS:
+            return self.memory[self.memory[self.ip + index]]
+        elif mode == PMode.IMM:
+            return self.memory[self.ip + index]
+    
+    def write_at(self, pos_offset, value):
+        output_pos = self.memory[self.ip + pos_offset]
+        self.memory[output_pos] = value
+    
+    def op_add(self):
+        self.write_at(3, self.param(1) + self.param(2))
+        self.ip += 4
+
+    def op_mul(self):
+        self.write_at(3, self.param(1) * self.param(2))
+        self.ip += 4
+
+    def op_in(self):
+        self.write_at(1, self.inputs.pop(0))
+        self.ip += 2
+
+    def op_out(self):
+        self.outputs.append(self.param(1))
+        if self.print_output:
+            print(">", self.outputs[-1])
+        self.ip += 2
+
+    def op_jnz(self):
+        if self.param(1) != 0:
+            self.ip = self.param(2)
+        else:
+            self.ip += 3
+
+    def op_jez(self):
+        if self.param(1) == 0:
+            self.ip = self.param(2)
+        else:
+            self.ip += 3
+
+    def op_lt(self):
+        self.write_at(3, int(self.param(1) < self.param(2)))
+        self.ip += 4
+
+    def op_eq(self):
+        self.write_at(3, int(self.param(1) == self.param(2)))
+        self.ip += 4
+
+    def op_halt(self):
+        self.halt = True