Solving Advent of Code 2019-06 with R (and no JavaScript this time).

[Disclaimer] Obviously, this post contains a big spoiler about Advent of Code, as it gives solutions for solving day 6.

Instructions

Find the instructions at: https://adventofcode.com/2019/day/6

R solution

Part one

library(magrittr)
library(igraph)

## 
## Attaching package: 'igraph'

## The following objects are masked from 'package:stats':
## 
##     decompose, spectrum

## The following object is masked from 'package:base':
## 
##     union

ipt <- read.delim("input6.txt", header = FALSE, sep = ")", stringsAsFactor = FALSE)
grph <- ipt %>% 
  graph_from_data_frame() 

grph %>% 
  distance_table() %>% 
  extract2("res") %>% 
  sum()

## [1] 147807

Part two

distances(
  grph, 
  v = V(grph)[["YOU"]], 
  to = V(grph)[["SAN"]]
) - 2

##     SAN
## YOU 229

JS solution

Nop, no JS solution today… I didn’t feel like reimplementing igraph in JavaScript, neither digging into the graph modules today 😉