Binary Search in Go

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

Current Solution

package main

import (
	"encoding/json"
	"fmt"
	"os"
	"regexp"
	"strconv"
	"strings"
)

func binarySearch(list []int, target int) bool {
	midIndex := len(list) / 2
	midpoint := list[midIndex]

	if midpoint == target {
		return true
	}

	if len(list) <= 1 {
		return false
	}

	if target < list[midIndex] {
		return binarySearch(list[:midIndex], target)
	}

	return binarySearch(list[midIndex:], target)
}

func verifySortedList(list []int) {
	lastVal := list[0]
	for _, val := range list {
		if val < lastVal {
			exitWithError()
		}
	}
}

func strToSliceInt(strList string) []int {
	list := regexp.MustCompile(", ?").Split(strList, -1)
	var nums []int
	for _, num := range list {
		n, err := strconv.Atoi(num)
		if err != nil {
			exitWithError()
		}
		nums = append(nums, n)
	}
	return nums
}

func sliceIntToString(list []int) (out string) {
	bytes, _ := json.Marshal(list)
	out = strings.Replace(string(bytes), ",", ", ", -1)
	out = strings.Trim(out, "[]")
	return
}

func exitWithError() {
	fmt.Println("Usage: please provide a list of sorted integers (\"1, 4, 5, 11, 12\") and the integer to find (\"11\")")
	os.Exit(1)
}

func main() {
	if len(os.Args) != 3 {
		exitWithError()
	}

	list := strToSliceInt(os.Args[1])
	verifySortedList(list)
	target, err := strconv.Atoi(os.Args[2])
	if err != nil {
		exitWithError()
	}
	fmt.Println(binarySearch(list, target))
}

Binary Search in Go was written by:

• Parker Johansen

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

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