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Day 8

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54
.github/README.md vendored
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@ -10,33 +10,33 @@ Go solutions are near direct copies of the Python solutions and may be added a f
<!-- PARSE START -->
| Day | | Python | Go |
| --------------------------- | ----------------------------- | ------------------------------------- | --------------------------------- |
| [1](/01-reportRepair) | ![Completed][check] | [Link](/01-reportRepair/python) | [Link](/01-reportRepair/go) |
| [2](/02-passwordPhilosophy) | ![Completed][check] | [Link](/02-passwordPhilosophy/python) | [Link](/02-passwordPhilosophy/go) |
| [3](/03-tobogganTrajectory) | ![Completed][check] | [Link](/03-tobogganTrajectory/python) | [Link](/03-tobogganTrajectory/go) |
| [4](/04-passportProcessing) | ![Completed][check] | [Link](/04-passportProcessing/python) | [Link](/04-passportProcessing/go) |
| [5](/05-binaryBoarding) | ![Completed][check] | [Link](/05-binaryBoarding/python) | [Link](/05-binaryBoarding/go) |
| [6](/06-customCustoms) | ![Completed][check] | [Link](/06-customCustoms/python) | [Link](/06-customCustoms/go) |
| [7](/07-handyHaversacks) | ![Completed][check] | [Link](/07-handyHaversacks/python) | [Link](/07-handyHaversacks/go) |
| 8 | ![Not yet attempted][pending] | | |
| 9 | | | |
| 10 | | | |
| 11 | | | |
| 12 | | | |
| 13 | | | |
| 14 | | | |
| 15 | | | |
| 16 | | | |
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| 18 | | | |
| 19 | | | |
| 20 | | | |
| 21 | | | |
| 22 | | | |
| 23 | | | |
| 24 | | | |
| 25 | | | |
| Day | | Python | Go |
| --------------------------- | ------------------- | ------------------------------------- | --------------------------------- |
| [1](/01-reportRepair) | ![Completed][check] | [Link](/01-reportRepair/python) | [Link](/01-reportRepair/go) |
| [2](/02-passwordPhilosophy) | ![Completed][check] | [Link](/02-passwordPhilosophy/python) | [Link](/02-passwordPhilosophy/go) |
| [3](/03-tobogganTrajectory) | ![Completed][check] | [Link](/03-tobogganTrajectory/python) | [Link](/03-tobogganTrajectory/go) |
| [4](/04-passportProcessing) | ![Completed][check] | [Link](/04-passportProcessing/python) | [Link](/04-passportProcessing/go) |
| [5](/05-binaryBoarding) | ![Completed][check] | [Link](/05-binaryBoarding/python) | [Link](/05-binaryBoarding/go) |
| [6](/06-customCustoms) | ![Completed][check] | [Link](/06-customCustoms/python) | [Link](/06-customCustoms/go) |
| [7](/07-handyHaversacks) | ![Completed][check] | [Link](/07-handyHaversacks/python) | [Link](/07-handyHaversacks/go) |
| [8](/08-handheldHalting) | ![Completed][check] | [Link](/08-handheldHalting/python) | [Link](/08-handheldHalting/go) |
| 9 | | | |
| 10 | | | |
| 11 | | | |
| 12 | | | |
| 13 | | | |
| 14 | | | |
| 15 | | | |
| 16 | | | |
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| 21 | | | |
| 22 | | | |
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| 24 | | | |
| 25 | | | |
<!-- PARSE END -->

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# [Day 8: Handheld Halting](https://adventofcode.com/2020/day/8)
<details><summary>Challenge description</summary>
*Description (c) [Eric Wastl](https://twitter.com/ericwastl)*
## Part One
Your flight to the major airline hub reaches cruising altitude without incident. While you consider checking the in-flight menu for one of those drinks that come with a little umbrella, you are interrupted by the kid sitting next to you.
Their [handheld game console](https://en.wikipedia.org/wiki/Handheld_game_console) won't turn on! They ask if you can take a look.
You narrow the problem down to a strange _infinite loop_ in the <span title="A trendy new line of encrypted footwear?">boot code</span> (your puzzle input) of the device. You should be able to fix it, but first you need to be able to run the code in isolation.
The boot code is represented as a text file with one _instruction_ per line of text. Each instruction consists of an _operation_ (`acc`, `jmp`, or `nop`) and an _argument_ (a signed number like `+4` or `-20`).
* `acc` increases or decreases a single global value called the _accumulator_ by the value given in the argument. For example, `acc +7` would increase the accumulator by 7\. The accumulator starts at `0`. After an `acc` instruction, the instruction immediately below it is executed next.
* `jmp` _jumps_ to a new instruction relative to itself. The next instruction to execute is found using the argument as an _offset_ from the `jmp` instruction; for example, `jmp +2` would skip the next instruction, `jmp +1` would continue to the instruction immediately below it, and `jmp -20` would cause the instruction 20 lines above to be executed next.
* `nop` stands for _No OPeration_ - it does nothing. The instruction immediately below it is executed next.
For example, consider the following program:
nop +0
acc +1
jmp +4
acc +3
jmp -3
acc -99
acc +1
jmp -4
acc +6
These instructions are visited in this order:
nop +0 | 1
acc +1 | 2, 8(!)
jmp +4 | 3
acc +3 | 6
jmp -3 | 7
acc -99 |
acc +1 | 4
jmp -4 | 5
acc +6 |
First, the `nop +0` does nothing. Then, the accumulator is increased from 0 to 1 (`acc +1`) and `jmp +4` sets the next instruction to the other `acc +1` near the bottom. After it increases the accumulator from 1 to 2, `jmp -4` executes, setting the next instruction to the only `acc +3`. It sets the accumulator to 5, and `jmp -3` causes the program to continue back at the first `acc +1`.
This is an _infinite loop_: with this sequence of jumps, the program will run forever. The moment the program tries to run any instruction a second time, you know it will never terminate.
Immediately _before_ the program would run an instruction a second time, the value in the accumulator is _`5`_.
Run your copy of the boot code. Immediately before any instruction is executed a second time, _what value is in the accumulator?_
Your puzzle answer was `1816`.
## Part Two
After some careful analysis, you believe that _exactly one instruction is corrupted_.
Somewhere in the program, _either_ a `jmp` is supposed to be a `nop`, _or_ a `nop` is supposed to be a `jmp`. (No `acc` instructions were harmed in the corruption of this boot code.)
The program is supposed to terminate by _attempting to execute an instruction immediately after the last instruction in the file_. By changing exactly one `jmp` or `nop`, you can repair the boot code and make it terminate correctly.
For example, consider the same program from above:
nop +0
acc +1
jmp +4
acc +3
jmp -3
acc -99
acc +1
jmp -4
acc +6
If you change the first instruction from `nop +0` to `jmp +0`, it would create a single-instruction infinite loop, never leaving that instruction. If you change almost any of the `jmp` instructions, the program will still eventually find another `jmp` instruction and loop forever.
However, if you change the second-to-last instruction (from `jmp -4` to `nop -4`), the program terminates! The instructions are visited in this order:
nop +0 | 1
acc +1 | 2
jmp +4 | 3
acc +3 |
jmp -3 |
acc -99 |
acc +1 | 4
nop -4 | 5
acc +6 | 6
After the last instruction (`acc +6`), the program terminates by attempting to run the instruction below the last instruction in the file. With this change, after the program terminates, the accumulator contains the value _`8`_ (`acc +1`, `acc +1`, `acc +6`).
Fix the program so that it terminates normally by changing exactly one `jmp` (to `nop`) or `nop` (to `jmp`). _What is the value of the accumulator after the program terminates?_
Your puzzle answer was `1149`.
</details>
<details><summary>Script output</summary>
```
❯ python .\python\
AoC 2020: day 8 - Handheld Halting
Python 3.8.5
Test cases
1.1 pass
2.1 pass
Answers
Part 1: 1816
Part 2: 1149
❯ go run .\go\
AoC 2020: day 8 - Handheld Halting
Go go1.15.2
Test cases
1.1 pass
2.1 pass
Answers
Part 1: 1816
Part 2: 1149
```
</details>

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08-handheldHalting/go/challenge/common.go Normal file
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package challenge
import (
"strconv"
"strings"
)
type Instruction struct {
Opcode string
Operand int
}
func NewInstruction(instr string) Instruction {
icp := strings.Split(instr, " ")
opc, err := strconv.Atoi(icp[1])
if err != nil {
panic(err)
}
return Instruction{
Opcode: icp[0],
Operand: opc,
}
}
func parse(instr string) (o []Instruction) {
for _, v := range strings.Split(strings.TrimSpace(instr), "\n") {
o = append(o, NewInstruction(v))
}
return
}

44
08-handheldHalting/go/challenge/partOne.go Normal file
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package challenge
func PartOne(instr string) int {
instructions := parse(instr)
var (
acc int
pc int
visited []int
)
for {
{
var found bool
for _, v := range visited {
if v == pc {
found = true
break
}
}
if found {
return acc
} else {
visited = append(visited, pc)
}
}
cir := instructions[pc]
if cir.Opcode == "jmp" {
pc += cir.Operand
} else {
switch cir.Opcode {
case "acc":
acc += cir.Operand
case "nop":
}
pc += 1
}
}
}

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08-handheldHalting/go/challenge/partTwo.go Normal file
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package challenge
func execute(instructions []Instruction) (cleanExit bool, acc int) {
var (
pc int
visited []int
)
for {
if pc >= len(instructions) {
// Clean exit
return true, acc
}
{
var found bool
for _, v := range visited {
if v == pc {
found = true
break
}
}
if found {
return false, acc
} else {
visited = append(visited, pc)
}
}
cir := instructions[pc]
if cir.Opcode == "jmp" {
pc += cir.Operand
} else {
switch cir.Opcode {
case "acc":
acc += cir.Operand
case "nop":
}
pc += 1
}
}
}
func PartTwo(instr string) int {
masterInstructions := parse(instr)
var switchSetLocations []int
for idx, instruction := range masterInstructions {
if instruction.Opcode == "jmp" || instruction.Opcode == "nop" {
switchSetLocations = append(switchSetLocations, idx)
}
}
for _, slc := range switchSetLocations {
// Copy instruction set
instructions := make([]Instruction, len(masterInstructions))
copy(instructions, masterInstructions)
// Swap instruction
oldval := instructions[slc].Opcode
var newval string
if oldval == "jmp" {
newval = "nop"
} else if oldval == "nop" {
newval = "jmp"
}
instructions[slc].Opcode = newval
// Execute
cleanExit, acc := execute(instructions)
if cleanExit {
return acc
}
}
return 0
}

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08-handheldHalting/go/main.go Normal file
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package main
import (
"adventOfCode/08-handheldHalting/go/challenge"
"encoding/json"
"fmt"
"io/ioutil"
"os"
"runtime"
"strconv"
"github.com/fatih/color"
)
func main() {
var infoStruct info
{
inb, err := ioutil.ReadFile("info.json")
if err != nil {
fmt.Println("Error: could not open info.json")
os.Exit(-1)
}
err = json.Unmarshal(inb, &infoStruct)
if err != nil {
fmt.Println("Error: could not parse info.json")
os.Exit(-1)
}
}
var (
year = infoStruct.Year
day = infoStruct.Day
title = infoStruct.Title
)
fmt.Fprintf(color.Output, "%s: day %s - %s\n", color.YellowString("AoC "+year), color.BlueString(day), title)
fmt.Fprintf(color.Output, "Go %s\n\n", color.BlueString(runtime.Version()))
var challengeInput string
{
inb, err := ioutil.ReadFile("input.txt")
if err != nil {
fmt.Println("Error: could not open input.txt")
os.Exit(-1)
}
challengeInput = string(inb)
}
runTests(infoStruct)
fmt.Println("Answers")
fmt.Fprintf(color.Output, "Part %s: %s\n", color.BlueString("1"), color.BlueString(strconv.Itoa(challenge.PartOne(challengeInput))))
fmt.Fprintf(color.Output, "Part %s: %s\n", color.BlueString("2"), color.BlueString(strconv.Itoa(challenge.PartTwo(challengeInput))))
}
type tc struct {
Input string `json:"input"`
Expected int `json:"expected"`
}
type info struct {
Year string `json:"year"`
Day string `json:"day"`
Title string `json:"title"`
TestCases struct {
One []tc `json:"one"`
Two []tc `json:"two"`
} `json:"testCases"`
}
func runTests(infoStruct info) {
if len(infoStruct.TestCases.One) == 0 && len(infoStruct.TestCases.Two) == 0 {
fmt.Println("Info: no test cases specified. Skipping tests")
fmt.Println()
return
}
fmt.Println("Test cases")
rt := func(tcs []tc, f func(string) int, n string) {
for i, tc := range tcs {
fmt.Fprintf(color.Output, "%s ", color.BlueString(n+"."+strconv.Itoa(i+1)))
result := f(tc.Input)
if result == tc.Expected {
fmt.Fprintf(color.Output, "%s", color.GreenString("pass"))
} else {
fmt.Fprintf(color.Output, "%s (got %s, expected %s)", color.RedString("fail"), color.BlueString(strconv.Itoa(result)), color.BlueString(strconv.Itoa(tc.Expected)))
}
fmt.Println()
}
}
rt(infoStruct.TestCases.One, challenge.PartOne, "1")
rt(infoStruct.TestCases.Two, challenge.PartTwo, "2")
fmt.Println()
}

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08-handheldHalting/info.json Normal file
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{
"year": "2020",
"day": "8",
"title": "Handheld Halting",
"testCases": {
"one": [
{
"input": "nop +0\nacc +1\njmp +4\nacc +3\njmp -3\nacc -99\nacc +1\njmp -4\nacc +6",
"expected": 5
}
],
"two": [
{
"input": "nop +0\nacc +1\njmp +4\nacc +3\njmp -3\nacc -99\nacc +1\njmp -4\nacc +6",
"expected": 8
}
]
}
}

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08-handheldHalting/input.txt Normal file
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jmp +149
acc -11
nop +95
acc -6
jmp +196
acc +2
acc -6
acc +38
acc +18
jmp +246
acc +43
acc +37
acc -1
jmp +390
acc +32
acc -15
jmp +487
jmp +382
jmp +71
jmp +331
acc -3
acc -12
acc +4
jmp +417
acc +30
acc +20
jmp +410
acc +22
acc +25
acc +19
acc +5
jmp +405
acc +15
acc +33
acc +7
acc -18
jmp +463
acc +25
acc +8
acc +1
jmp +64
jmp +1
jmp +562
jmp +4
acc +21
acc +12
jmp +467
nop +197
acc +32
jmp +7
acc +2
jmp +352
acc +15
jmp +289
acc +39
jmp +448
jmp +227
acc +17
acc +4
jmp +326
acc -1
nop +167
acc +30
nop +471
jmp +101
acc +45
nop +276
acc +12
jmp +215
nop +80
acc +23
acc +31
jmp +104
acc +39
acc +15
jmp +40
nop +433
acc +21
acc +22
acc +37
jmp +421
acc +14
jmp -30
acc +42
acc +38
jmp +203
acc -8
acc +27
jmp +102
acc -5
acc +0
acc +18
acc +26
jmp +212
acc +25
acc +18
jmp +209
acc +18
acc +44
acc +47
nop -40
jmp +372
acc +29
jmp +384
acc +39
acc -11
acc +43
jmp +406
acc +2
nop +439
jmp +343
acc +29
acc +18
jmp +457
jmp -31
jmp +146
acc +12
acc +26
nop +98
jmp +125
acc +6
acc +35
acc +48
acc +44
jmp +497
acc +17
acc -8
jmp +223
acc +47
jmp +405
jmp +212
jmp +317
acc -13
acc -6
jmp +94
acc +47
acc +50
acc -16
acc +38
jmp +290
jmp +383
nop -44
acc +38
nop +418
acc +42
jmp +233
nop -94
acc +46
jmp +413
acc +10
acc -6
jmp +410
acc +30
jmp -93
acc -13
jmp +6
acc -16
acc +18
nop +403
acc +0
jmp +68
acc +45
jmp +302
acc +5
jmp +26
acc -5
acc +49
jmp +412
acc +3
acc +14
jmp +278
acc +6
acc +4
jmp -58
acc +14
jmp -60
acc -12
acc +23
jmp +225
acc +9
acc +17
acc -10
acc -13
jmp +216
acc -8
nop +363
jmp +84
nop +300
acc -15
jmp +415
acc +17
acc -11
nop +96
jmp +377
nop +259
acc +4
jmp +327
acc +0
jmp +149
jmp +12
acc +23
acc +43
acc +2
jmp +1
jmp +400
acc +24
jmp +114
acc +3
acc -13
jmp +149
jmp +100
jmp +1
jmp +157
acc +23
acc -15
jmp -139
nop -85
jmp +201
acc -2
acc +39
acc +30
nop -93
jmp -11
acc +46
jmp +285
jmp +1
acc +41
jmp +115
acc +48
acc -12
acc -17
jmp -15
nop +82
acc +25
jmp -151
acc +20
acc -14
acc +9
acc -9
jmp +284
acc +27
acc +38
acc +50
jmp +145
nop +279
jmp -55
nop +245
jmp +254
acc +4
jmp +368
nop -119
acc -11
acc +16
acc +19
jmp -54
nop -186
nop -187
acc +9
acc +44
jmp -222
jmp +253
nop -234
acc +33
acc +35
acc -17
jmp +11
acc +2
acc +41
acc +47
jmp +310
acc +0
acc -8
acc +1
jmp +55
acc -1
jmp -257
acc +7
acc +44
nop +253
acc +41
jmp +302
acc +16
jmp -185
jmp +140
jmp +1
nop +3
acc +35
jmp -267
acc +6
jmp -269
jmp +211
acc +30
acc +14
acc +16
acc +41
jmp -47
jmp -192
nop -21
acc -1
jmp +192
acc -6
acc +15
acc +3
nop -247
jmp -88
jmp +164
acc +47
nop +43
acc +40
jmp +151
jmp +85
jmp +1
acc +40
jmp -257
acc +13
acc +13
jmp -256
acc +25
acc +39
jmp +260
acc +13
acc -18
acc -19
acc -14
jmp -10
acc -16
acc +9
jmp -199
nop +185
acc +38
jmp -261
nop +200
acc -18
nop +115
acc +36
jmp -259
acc +47
acc -2
acc +9
jmp -139
nop -117
jmp -13
jmp +1
jmp +247
acc +19
acc +49
jmp +177
acc -1
jmp +249
jmp -218
acc +12
acc +33
jmp +108
jmp -48
nop -205
acc +32
jmp -159
jmp -129
acc +32
jmp +1
jmp +249
nop +75
acc +17
acc -16
jmp +253
acc -9
jmp -12
acc +15
jmp -14
acc +13
acc -8
nop -13
jmp +27
nop -336
acc +33
acc +10
acc -1
jmp -350
nop -134
acc -11
jmp +5
acc +10
acc +13
acc +13
jmp -249
acc +8
jmp -215
jmp +49
acc +35
acc +28
jmp -54
acc +14
nop -264
jmp +1
jmp -166
jmp -291
acc +9
acc +43
jmp -301
nop +149
acc -9
jmp -81
jmp -287
acc +9
acc +35
acc -12
jmp -295
acc +46
jmp -394
acc +29
acc +19
acc +9
jmp -58
acc +7
acc +32
nop -261
acc +44
jmp -365
jmp +1
jmp +120
acc +37
nop -177
jmp +101
acc +42
acc +13
acc +36
jmp -343
acc +45
jmp -408
acc +23
acc +0
jmp -66
jmp +1
acc +34
acc +19
jmp +104
jmp +1
acc +36
jmp -141
jmp -44
acc +9
acc +30
acc +18
acc +0
jmp -303
jmp +1
acc +12
jmp +66
acc +0
jmp +82
acc +43
acc +18
jmp +49
acc -16
acc -3
acc +0
jmp -249
acc -2
nop +81
jmp +40
jmp +94
acc -16
acc +1
jmp -445
jmp +1
acc +22
jmp -130
acc +44
jmp -73
acc +3
acc +5
jmp -121
jmp -352
jmp -163
acc +15
acc +47
nop +141
jmp +140
acc -18
nop -289
acc +16
jmp -476
acc -19
nop +134
acc -10
acc +37
jmp -13
jmp -359
acc +32
acc +14
jmp -306
acc +25
acc +30
jmp -441
acc +44
acc +14
acc +12
acc +19
jmp -387
jmp -12
jmp -180
jmp -113
jmp -29
acc +34
acc -13
acc -12
nop +73
jmp -263
jmp -373
jmp -360
acc +38
nop -123
jmp -176
nop -155
acc -11
acc +32
nop +54
jmp -461
acc +31
acc +10
acc -7
acc -19
jmp -212
acc +41
acc +4
nop -2
jmp -483
acc +16
acc +42
acc -15
jmp -286
jmp -122
acc -4
jmp -436
acc +27
jmp -508
acc +38
nop -309
jmp +10
acc +31
acc +18
acc +5
jmp -119
acc +8
acc -7
acc -16
acc +18
jmp -416
acc -15
acc +1
acc +30
acc +8
jmp -476
jmp -298
acc +29
acc +24
acc -9
acc +35
jmp -438
nop -5
jmp -100
acc +5
acc +3
acc +5
acc -4
jmp +14
acc +43
acc +3
acc +40
jmp -517
acc +10
acc +35
acc +38
jmp -120
acc +1
acc -18
acc +0
acc +42
jmp -69
jmp -101
acc +1
jmp -271
acc +37
acc +17
jmp +1
jmp -401
acc +1
acc +3
acc -8
jmp -392
nop -99
acc +2
jmp -301
acc +10
acc +32
acc +3
jmp -286
jmp +1
jmp -444
nop -364
acc +46
acc +30
acc -2
jmp -13
nop -65
acc +22
jmp -292
acc -13
jmp -480
acc +4
acc -8
nop -500
jmp -113
acc -16
acc +40
acc -18
jmp -125
jmp -482
acc +28
acc -5
jmp -471
acc +33
acc +49
acc +21
acc +9
jmp +1

66
08-handheldHalting/python/__main__.py Normal file
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import json
import platform
import sys
from rich import print
from partOne import partOne
from partTwo import partTwo
def run_tests(test_cases):
do_tests = True
if len(test_cases) == 0:
do_tests = False
elif len(test_cases["one"]) == 0 and len(test_cases["two"]) == 0:
do_tests = False
if not do_tests:
print("Info: no test cases specified. Skipping tests\n")
return
print("Test cases")
def rt(tcs, f, n):
for i, tc in enumerate(tcs):
print(f"{n}.{i+1} ", end="")
expectedInt = tc["expected"]
result = f(str(tc["input"]))
if result == expectedInt:
print("[green]pass[/green]")
else:
print(f"[red]fail[/red] (got {result}, expected {expectedInt})")
rt(test_cases["one"], partOne, 1)
rt(test_cases["two"], partTwo, 2)
print()
if __name__ == "__main__":
try:
info = open("info.json").read()
except FileNotFoundError:
print("Error: could not open info.json")
sys.exit(-1)
info = json.loads(info)
year = info["year"]
day = info["day"]
title = info["title"]
print(f"[yellow]AoC {year}[/yellow]: day {day} - {title}")
print(f"Python {platform.python_version()}\n")
try:
challenge_input = open("input.txt").read()
except FileNotFoundError:
print("Error: could not open input.txt")
sys.exit(-1)
run_tests(info["testCases"])
print("Answers")
print("Part 1:", partOne(challenge_input))
print("Part 2:", partTwo(challenge_input))

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08-handheldHalting/python/common.py Normal file
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from typing import List
class Instruction:
opcode: str
operand: int
def __init__(self, instr: str) -> None:
self.opcode, t = instr.split(" ")
self.operand = int(t)
def parse(instr: str) -> List[Instruction]:
return [Instruction(x) for x in instr.strip().split("\n")]

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08-handheldHalting/python/partOne.py Normal file
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from common import *
def partOne(instr: str) -> int:
instructions = parse(instr)
acc = 0
pc = 0
visited = [] # indexes of visited instructions
while True:
if pc in visited:
return acc
else:
visited.append(pc)
cir = instructions[pc]
if cir.opcode == "jmp":
pc += cir.operand
else:
if cir.opcode == "acc":
acc += cir.operand
elif cir.opcode == "nop":
pass
pc += 1

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08-handheldHalting/python/partTwo.py Normal file
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import copy
from typing import List, Tuple
from common import *
def execute(instructions: List[Instruction]) -> Tuple[bool, int]:
# Returning false means a loop occured. Returning true means no loop occured.
# The value of the accumulator is always returned
acc = 0
pc = 0
visited = [] # indexes of visited instructions
while True:
if pc >= len(instructions):
# Clean exit
return True, acc
if pc in visited:
# Loop is going to occur at some point
return False, acc
else:
visited.append(pc)
cir = instructions[pc]
if cir.opcode == "jmp":
pc += cir.operand
else:
if cir.opcode == "acc":
acc += cir.operand
elif cir.opcode == "nop":
pass
pc += 1
def partTwo(instr: str) -> int:
master_instructions = parse(instr)
# I imagine there's probably a smart way to do this... but I'm going to bruteforce it haha
# Build list of locations of instructions to be switched
switch_set_locations = []
for idx, instruction in enumerate(master_instructions):
if instruction.opcode in ["jmp", "nop"]:
switch_set_locations.append(idx)
for slc in switch_set_locations:
instructions = copy.deepcopy(master_instructions)
# Switch instruction
oldval = instructions[slc].opcode
instructions[slc].opcode = "jmp" if oldval == "nop" else "nop"
# Execute
clean_exit, acc = execute(instructions)
if clean_exit:
break
return acc