Binary Search in Euphoria

Published on 19 February 2023 (Updated: 19 February 2023)

Welcome to the Binary Search in Euphoria page! Here, you'll find the source code for this program as well as a description of how the program works.

Current Solution

include std/io.e
include std/types.e
include std/text.e
include std/get.e as stdget
include std/sequence.e
include std/search.e
include std/utils.e

-- Indices for value() return value
enum VALUE_ERROR_CODE, VALUE_VALUE, VALUE_NUM_CHARS_READ

-- Indices for parse_int() return value
enum PARSE_INT_VALID, PARSE_INT_VALUE

function parse_int(sequence s)
    -- Trim off whitespace and parse string
    s = trim(s)
    sequence result = stdget:value(s,, GET_LONG_ANSWER)

    -- Error if any errors, value is not an integer, or any leftover characters
    boolean valid = (
        result[VALUE_ERROR_CODE] = GET_SUCCESS
        and integer(result[VALUE_VALUE])
        and result[VALUE_NUM_CHARS_READ] = length(s)
    )

    -- Get value if invalid
    integer value = 0
    if valid
    then
        value = result[VALUE_VALUE]
    end if

    return {valid, value}
end function

-- Indices for parse_int_list() return value
enum PARSE_INT_LIST_VALID, PARSE_INT_LIST_VALUES

function parse_int_list(sequence s)
    -- Split string on comma
    sequence list = split(s, ",")

    -- Parse each item
    integer valid = FALSE
    sequence values = {}
    for n = 1 to length(list)
    do
        sequence result = parse_int(list[n])
        valid = result[PARSE_INT_VALID]
        values &= result[PARSE_INT_VALUE]
        if not valid
        then
            exit
        end if
    end for

    return {valid, values}
end function

procedure usage()
    puts(
        STDOUT, 
        "Usage: please provide a list of sorted integers (\"1, 4, 5, 11, 12\") and the integer to find (\"11\")\n"
    )
    abort(0)
end procedure

function check_sorted(sequence values)
    for k = 1 to length(values) - 1
    do
        if values[k] > values[k + 1]
        then
            return FALSE
        end if
    end for

    return TRUE
end function

-- Check command-line arguments
sequence argv = command_line()
if length(argv) < 5 or length(argv[4]) = 0 or length(argv[5]) = 0
then
    usage()
end if

-- Parse 1st command-line argument
sequence list_result = parse_int_list(argv[4])
sequence values = list_result[PARSE_INT_LIST_VALUES]
if not list_result[PARSE_INT_LIST_VALID]
then
    usage()
end if

-- Parse 2nd command-line argument
sequence result = parse_int(argv[5])
integer target = result[PARSE_INT_VALUE]
if not result[PARSE_INT_VALID]
then
    usage()
end if

-- Make sure list is sorted
if not check_sorted(values)
then
    usage()
end if

-- Use built-in binary search and show results
integer index = binary_search(target, values)
puts(STDOUT, iif(index > 0, "true\n", "false\n"))

Binary Search in Euphoria was written by:

If you see anything you'd like to change or update, please consider contributing.

How to Implement the Solution

No 'How to Implement the Solution' section available. Please consider contributing.

How to Run the Solution

No 'How to Run the Solution' section available. Please consider contributing.