Check digit of numbers

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nimcache

README.md

Check digit of numbers

This program is a program to calculate the check digit of many numbers.

Basic usage

First prepare a file in which numbers are written.
After that, we will load the file into the program.

10001
10002
10003
.....
.....

When loading it, the number with the check digit should be displayed.

cat numbers.txt | check_digit

Verify the number with check digit, use the -c, --check option.

cat numbers.txt | check_digit -c

Build

To execute the build, execute the following command.

make build

To execute the build for the release, execute the following command.

make release

Test

The test can be executed with the following command.

make test

Licence

The MIT Licence

checkdigit.nim

#[
  checkdigit.nim

  Noritaka Horio <holy.shared.design@gmail.com>

  Copyright (c) 2017 Noritaka Horio

  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:

  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  THE SOFTWARE.
]#

import strutils, sequtils

# Odd/Even number list
type NumberSet = tuple[odd: seq[int], even: seq[int]]

# Check Digit result
type CheckDigitResult = tuple[input: string, checkDigit: int]

proc isOdd(n: int): bool =
  n mod 2 == 0

#
# Collect odd/event number of original number
#
proc collectNumbers(number: string): NumberSet =
  var odd_numbers, even_numbers: seq[int] = @[]

  for pos in 0..(len(number) - 1):
    let next = pos + 1
    let v = parseInt(number[pos..pos])
    if isOdd(next):
      odd_numbers.add(v)
    else:
      even_numbers.add(v)
  (odd: odd_numbers, even: even_numbers)

#
# Calculate check digit
#
proc ofNumber*(number: string): CheckDigitResult =
  let numbers = collectNumbers(number)
  let odd_sum = foldl(numbers.odd, a + b)
  let even_sum = foldl(numbers.even, a + b)
  let odd_even_sum = odd_sum + (even_sum * 3)

  let str_num = intToStr(odd_even_sum)
  let last_index = len(str_num) - 1

  let last_num = parseInt(str_num[last_index..last_index])

  var check_digit = 0
  if last_num == 0:
    check_digit = 0
  else:
    check_digit = 10 - last_num

  (input: number, checkDigit: checkDigit)

proc isValid*(number: string): bool =
  let last_index = len(number) - 1
  let last_check_digit = parseInt(number[last_index..last_index])
  let check_digit = ofNumber(number[0..(last_index - 1)])
  check_digit.checkDigit == last_check_digit

checkdigit_test.nim

import unittest, checkdigit

suite "checkdigit module":
  test "calucate check digit":
    let result = ofNumber("10000")
    check(result.input == "10000")
    check(result.checkDigit == 7)

  test "check valid digit":
    check(isValid("100007"))
    check(isValid("435451"))
    check(isValid("567787"))
    check(isValid("567671"))

main.nim

#[
  main.nim

  Noritaka Horio <holy.shared.design@gmail.com>

  Copyright (c) 2017 Noritaka Horio

  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:

  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  THE SOFTWARE.
]#

import parseopt, checkdigit

const PROGRAM_NAME = "checkdigit"
const PROGRAM_VERSION = "1.0.0"
const PROGRAM_AUTHOR = "Noritaka Horio <holy.shared.design@gmail.com>"
const PROGRAM_LICENCE = "The MIT Licence"

type CheckDigitAction = proc(number: string): void

proc writeHelp(): void =
  echo "Usage ", PROGRAM_NAME, "\n"
  echo "  checkdigit [OPTIONS]\n"
  echo "EXAMPLE:\n"
  echo "  cat number.txt | ", PROGRAM_NAME, " [OPTIONS]\n"
  echo """OPTIONS:
  -c, --check    Validate the check digit
  -v, --version  Displays the version of the program
  -h, --help     Display program help
  """
  quit(QuitSuccess)

proc writeVersion(): void =
  echo PROGRAM_NAME, " ", PROGRAM_VERSION
  echo "Author: ", PROGRAM_AUTHOR
  echo "Licence: ", PROGRAM_LICENCE
  quit(QuitSuccess)

proc printCheckDigit(number: string): void =
  let result = checkdigit.ofNumber(number)
  echo result.input, result.checkDigit

proc printInvalidCheckDigit(number: string): void =
  if checkdigit.isValid(number): return
  echo number

var check: CheckDigitAction = printCheckDigit

for kind, key, val in getopt():
  case kind
  of cmdArgument:
    continue
  of cmdLongOption, cmdShortOption:
    case key
    of "check", "c": check = printInvalidCheckDigit
    of "help", "h": writeHelp()
    of "version", "v": writeVersion()
  of cmdEnd: assert(false)

while endOfFile(stdin) == false:
  let number = readLine(stdin)
  check(number)

Makefile

build:
	nim compile main.nim
	mv main checkdigit

release:
	nim compile -d:release main.nim
	mv main checkdigit

test:
	nim compile checkdigit_test.nim
	./checkdigit_test

clean:
	rm nimcache/*
	rm checkdigit
	rm checkdigit_test

number_with_check_digit.txt

435451
567787
567671
778893
345460

numbers.txt

43545
56778
56767
77889
34546