A toy example of RSA encryption and decryption

rsa-example.R

#!/usr/bin/env Rscript
# rsa-example.R
#
# Inspired by Alex Van de Sande
# https://twitter.com/avsa/status/1318672796415819776

last_digit <- function(x) {
  x_char <- as.character(x)
  as.numeric(substr(x_char, nchar(x_char), nchar(x_char)))
}
# Pick a number between 0-9 for input
input <- 2
private_key <- 7
encrypted <- input ^ 3
output <- last_digit(last_digit(encrypted) ^ private_key)
input == output