Finish 2017.

2017/d23.py

@@ -0,0 +1,108 @@
+import subprocess
+from collections import defaultdict
+
+
+def print_game(regs, i, insts):
+    print("\033[H\033[J", end="")
+    for j, inst in enumerate(insts):
+        start = "  "
+        if j == i:
+            start = "> "
+        print(f"{start} {' '.join(inst)}")
+    for c in "abcdefgh":
+        print(c, regs[c])
+
+
+def part_1(data):
+    regs = {c: 0 for c in "abcdefgh"}
+    insts = list(map(lambda line: line.split(), data.splitlines()))
+
+    i = 0
+    while i < len(insts):
+        inst = insts[i]
+        match inst:
+            case ["set", reg, val]:
+                regs[reg] = regs[val] if val in regs else int(val)
+            case ["sub", reg, val]:
+                regs[reg] -= regs[val] if val in regs else int(val)
+            case ["mul", reg, val]:
+                regs[reg] *= regs[val] if val in regs else int(val)
+            case ["jnz", reg, val]:
+                val = regs[val] if val in regs else int(val)
+                assert type(val) is int
+                if val != 0:
+                    i += (val - 1)
+            case _:
+                assert False
+        i += 1
+
+
+def to_c(data):
+    insts = list(map(lambda line: line.split(), data.splitlines()))
+
+    label_count = 0
+    labels = defaultdict(list)
+    for i, inst in enumerate(insts):
+        match inst:
+            case ["jnz", reg, val]:
+                label = f"label_{label_count}"
+                label_count += 1
+                inst[2] = label
+                label_i = i + int(val)
+                labels[label_i].append(label)
+            case _:
+                pass
+
+    i = 0
+    begin = ["#include <stdio.h>", "", 
+             "int mul(int a, int b) {",
+             "    return a * b;",
+             "}",
+             "",
+             "int main() {" ]
+    decls = "    int "
+    for v in "abcdefgh":
+        decls += f"{v} = 0, "
+    decls = decls[:-2] + ";"
+    begin.append(decls)
+    body = []
+    end = [ "    return 0;", "}", ]
+
+    for i, inst in enumerate(insts):
+        if i in labels:
+            for label in labels[i]:
+                body.append(label + ":")
+        match inst:
+            case ["set", reg, val]:
+                body.append(f"    {reg} = {val};")
+            case ["sub", reg, val]:
+                body.append(f"    {reg} -= {val};")
+            case ["mul", reg, val]:
+                body.append(f"    {reg} = mul({reg}, {val});")
+            case ["jnz", reg, val]:
+                body.append(f"    if ({reg} != 0) goto {val};")
+            case _:
+                assert False
+    body.append(labels[i + 1][0] + ":")
+
+    all = begin + body + end
+    with open("i23.c", "w") as f:
+        for line in all:
+            f.write(line + "\n")
+
+def run_c():
+    subprocess.call(["gcc", "i23.c"])
+    subprocess.call(["./a.out"])
+    subprocess.call(["rm", "a.out"])
+
+
+def main():
+    with open("i23.txt") as f:
+        data = f.read()
+    # to_c(data)
+    # part_1(data)
+    run_c()
+
+
+if __name__ == "__main__":
+    main()

2017/d25.py

@@ -0,0 +1,58 @@
+from lib import str_to_int
+from collections import defaultdict
+
+
+def part_1(data):
+    rules = {}
+    steps = None
+    start_state = None
+    current_state = None
+    current_value = None
+    for line in data.splitlines():
+        if line.startswith("In state"):
+            current_state = line[-2]
+            rules[current_state] = {}
+        elif "current value" in line:
+            current_value = str_to_int(line)
+            rules[current_state][current_value] = []
+        elif "- Write the value" in line:
+            rules[current_state][current_value].append(str_to_int(line))
+        elif "- Move one slot to the right" in line:
+            rules[current_state][current_value].append(1)
+        elif "- Move one slot to the left" in line:
+            rules[current_state][current_value].append(-1)
+        elif "Continue with state" in line:
+            rules[current_state][current_value].append(line[-2])
+        elif "Begin in state" in line:
+            start_state = line[-2]
+        elif "checksum after" in line:
+            steps = str_to_int(line)
+        elif line.strip() == "":
+            pass
+        else:
+            print(line)
+            assert False
+
+    assert type(steps) is int
+    assert start_state is not None
+    current_state = start_state
+    tape = defaultdict(int)
+    pos = 0
+    for _ in range(steps):
+        current_value = tape[pos]
+        write_value, move, next_state = rules[current_state][current_value]
+        tape[pos] = write_value
+        pos += move
+        current_state = next_state
+
+    print(sum(tape.values()))
+
+
+def main():
+    with open("i25.txt") as f:
+        data = f.read()
+    part_1(data)
+
+
+if __name__ == "__main__":
+    main()

2017/i23.c

@@ -0,0 +1,65 @@
+#include <stdio.h>
+
+unsigned int mul_count = 0;
+
+int mul(int a, int b) {
+    mul_count++;
+    return a * b;
+}
+
+int main() {
+    for (int a = 0; a < 2; a++) {
+        int b = 0, c = 0, d = 0, e = 0, f = 0, g = 1, h = 0;
+        b = 67;
+        c = b;
+        if (a != 0) {
+            b = mul(b, 100);
+            b += 100000;
+            c = b;
+            c += 17000;
+        }
+
+        while (1) {
+            f = 1;
+            d = 2;
+
+            while (g != 0)
+            {
+                e = 2;
+                while (g != 0) {
+                    if (b % d == 0) {
+                        int e_required = b / d;
+                        if (e_required >= 2 && e_required <= b) {
+                            f = 0;
+                        }
+                    }
+                    mul_count += (b - e);
+                    g = 0;
+                }
+
+                d += 1;
+                g = d;
+                g -= b;
+            }
+
+            if (f == 0) {
+                h += 1;
+            }
+
+            g = b;
+            g -= c;
+            if (g != 0) {
+                b += 17;
+            } else {
+                break;
+            }
+        }
+        if (a == 0) {
+            printf("%d\n", mul_count);
+        } else {
+            printf("%d\n", h);
+        }
+    }
+
+    return 0;
+}

README.md

@@ -83,6 +83,6 @@ written in Python.
 - Day 20: 9:55 (would have been 10th)
 - Day 21: 90:00
 - Day 22: 25:00
-- Day 23:
+- Day 23: Multiple days... but super fun.
 - Day 24: 15:45 (48th)
-- Day 25:
+- Day 25: 41:00