An example of implementing binary search in Go

README.md

Binary Search implementation in Go

• $ go run main.go Returns a bool if the search value was found or not

main.go

// Find elements within a list by conistently reducing the
// amount of data to be searched
package main

import (
        "log"
        "sort"
        "sync"
)

// median is the middle index of the slice
// high is the upper bound, len(arr) -1
// low is the lower bound, 0

func main() {
        n1 := 2
        n2 := 10
        s1 := []int{1, 2, 3, 9, 4, 11, 7, 20}
        s2 := []int{10, 12, 13, 9, 4, 11, 7, 21}
        wg := new(sync.WaitGroup)

        go binarySearch(n1, s1, wg)
        go binarySearch(n2, s2, wg)

        wg.Add(2)
        wg.Wait()
}

// Search slice for the value of n
func binarySearch(n int, s []int, wg *sync.WaitGroup) {
        low := 0
        high := len(s) - 1

        // If low <= high, search for n
        sort.Ints(s)
        for low <= high {
                median := (low + high) / 2
                // If n is less than median, search lower
                if s[median] < n {
                        low = median + 1
                } else {
                        high = median - 1
                }
        }

        // n wasn't found in slice
        if low == len(s) || s[low] != n {
                log.Printf("Didn't find %v", n)
        } else {
                log.Printf("Found %v", n)
        }
        wg.Done()
}