2023 advent of code day 8

day_8.R

# first star
network <- read.table("nodes.txt", header = TRUE, sep = "\n")
edges <- as.numeric(factor(unlist(strsplit(colnames(network)[1], "")))) + 1
network$node <- sapply(strsplit(gsub("[^A-Z]", " ", network[, 1]), "\\s+"), "[", 1)

network$left_node <- sapply(strsplit(gsub("[^A-Z]", " ", network[, 1]), "\\s+"), "[", 2)
network$right_node <- sapply(strsplit(gsub("[^A-Z]", " ", network[, 1]), "\\s+"), "[", 3)
network <- network[, c(2:4)]

follow <- function(node, end_node = "ZZZ") {
  steps <- 0
  while (node != end_node) {
    node <- network[network$node==node, edges[steps %% length(edges) + 1]]
    steps <- steps + 1
    }
    steps
}
  follow("AAA")