Day 1: Chronal Calibration

Reference

Part One

library(tidyverse)
input <- read_lines(file = "inputs/2018/01.txt") |> as.integer()

cat(sum(input))
## 466

Part Two

# 136 found after some trials, using optimal value to optimize execution
frequencies <- tibble(change = rep(input, times = 136),
                      result = cumsum(change)) |> 
    rowid_to_column("time")

frequencies |> 
    group_by(result) |> 
    summarise(count = n(), second_time = nth(time, 2)) |> 
    filter(count > 1) |> 
    arrange(second_time) |> 
    head(1) |> 
    pull(result) |> 
    cat()
## 750