Project Euler 22: Names Scores

Using names.txt, a 46K text file containing over five-thousand first names, begin by sorting it into alphabetical order. Then working out the alphabetic value for each name, multiply this value by its alphabetical position in the list to obtain a name score.

For example, when the list is sorted into alphabetical order, COLIN, which is worth 3 + 15 + 12 + 9 + 14 = 53, is the 938^th name in the list. So, COLIN would obtain a score of 938 × 53 = 49714.

What is the total of all the name scores in the file?

This code reads and cleans the file and sorts the names alphabetically. The charToRaw function determines the numerical value of each character in each name. This output of this function is the hex ASCII code for each character. The letter A is number 65, so we subtract 64 from each value to get the sum total.

ProjectEuler

  ## Project Euler 22: Names Scores
  names <- readLines("https://projecteuler.net/project/resources/p022_names.txt",
                     warn =FALSE)
  names <- unlist(strsplit(names, ","))
  names <- gsub("[[:punct:]]", "", names)
  names <- sort(names)

  # Total Name scores
  answer <- 0
  for (i in names) {
      value <- sum(sapply(unlist(strsplit(i, "")),
                   function(x) as.numeric(charToRaw(x)) - 64))
      value <- value * which(names==i)
      answer <- answer + value
  }
  print(answer)

Modern computers in a globalised world don't use ASCII because it cannot encode the tens of thousands of characters that are needed for the world's languages. The video below explains the Unicode system to encode the world's symbols.