2018-01: Chronal Calibration

https://adventofcode.com/2018/day/1

library(data.table)
dt <- fread("input.txt")
head(dt)

    V1
1: -14
2:  15
3:   9
4:  19
5:  18
6:  14

Part 1

sum(dt$V1)

[1] 425

Part 2

breakFlag <- FALSE
re_pete <- 1
while (!breakFlag) {
  vec <- cumsum(rep(dt$V1, re_pete))
  
  twice <- vec[duplicated(vec)]
  
  if (length(twice >= 1)) {
    print(twice[1])
    breakFlag <- TRUE
  } else {
    re_pete <- re_pete + 1
  }
}

[1] 57538