17
https://adventofcode.com/2024/day/17
Prob1
python
import sys
reg_a = 0
reg_b = 0
reg_c = 0
def combo_operand(v: int):
if v >= 0 and v <= 3:
return v
if v == 4:
return reg_a
elif v == 5:
return reg_b
elif v == 6:
return reg_c
raise RuntimeError('operand 7')
op_list = []
for line in sys.stdin:
line = line.strip()
if not line:
continue
if line.startswith('Register'):
v = int(line[len('Register A: '):])
if line.startswith('Register A:'):
reg_a = v
elif line.startswith('Register B:'):
reg_b = v
else:
reg_c = v
else:
op_list = list(map(int, line.removeprefix('Program: ').split(',')))
output = []
ptr = 0
while ptr < len(op_list):
opcode = op_list[ptr]
operand = op_list[ptr + 1]
if opcode == 0:
reg_a >>= combo_operand(operand)
ptr += 2
elif opcode == 1:
reg_b ^= operand
ptr += 2
elif opcode == 2:
reg_b = combo_operand(operand) % 8
ptr += 2
elif opcode == 3:
if reg_a == 0:
ptr += 2
continue
ptr = operand
elif opcode == 4:
reg_b ^= reg_c
ptr += 2
elif opcode == 5:
output.append(combo_operand(operand) % 8)
ptr += 2
elif opcode == 6:
reg_b = reg_a >> combo_operand(operand)
ptr += 2
elif opcode == 7:
reg_c = reg_a >> combo_operand(operand)
ptr += 2
else:
raise RuntimeError('opcode = %d' % opcode)
print(','.join(map(str, output)))Prob2
go
package main
import (
"log"
)
func run2(a int64) []int {
output := []int{}
for a > 0 {
b := (a % 8) ^ 5
c := a >> b
b ^= c
a >>= 3
b ^= 6
output = append(output, int(b%8))
}
return output
}
func main() {
opList := []int{2, 4, 1, 5, 7, 5, 4, 5, 0, 3, 1, 6, 5, 5, 3, 0}
ansList := []int64{0}
for ptr := len(opList) - 1; ptr >= 0; ptr-- {
newAnsList := []int64{}
for _, ans := range ansList {
for i := range 8 {
newAns := ans*8 + int64(i)
res := run2(newAns)
if len(res) > 0 && res[0] == opList[ptr] {
newAnsList = append(newAnsList, newAns)
}
}
}
ansList = newAnsList
log.Println(ansList)
}
ans := ansList[0]
for _, aa := range ansList {
ans = min(aa, ans)
}
log.Println(ans)
}