# Binary Search in Golang and  Linear search method


## Algorithms in Golang

Algorithms and data structure is a big portion of our code, and starting out you might come across **Binary Search** as one of your lessons, If you are into Go, consider this code, as it helps you solve this common question.

## Calculating mid in binary search

Most cases when you write a binary search you make the mistake of using `(low + high )/ 2` and while this is valid for uint, unsigned integers (0, 255), you may in certain cases, run to a integers (-128, 127) where you run to some weird issues, this code will demonstrate that for you
```Go

func main() {

	var low int8 = 80
	var high int8 = 120
	var mid int8

	mid = (low + (high-low)/2)
	fmt.Println(mid)
	mid = (high + low) / 2
	fmt.Println(mid)
}
```
Console prints out:

> 100

> -28

[**try it out**](https://go.dev/play/p/h7HJxpTP-BV)

If you need more informations, No one is better than [Joshua Bloch](https://en.wikipedia.org/wiki/Joshua_Bloch) article, at [Google blog](https://ai.googleblog.com/2006/06/extra-extra-read-all-about-it-nearly.html)

[Binary Search in Golang and Linear Search method](https://gist.github.com/mohamedallam1991/53ed09e20ec19bcb3aa4e036c3f35d3a)

```go
package main

import "fmt"

func main() {
	b := []int{2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 100, 159, 192, 350, 1230, 1341, 4533}

	fmt.Println(BinarySearch(b, 31))
	fmt.Println(LinearSearch(b, 31))

}

func BinarySearch(haystack []int, needle int) bool {
	var high, low, mid, val int
	low = 0
	high = len(haystack)
	for low < high {
		mid = (low + ((high - low) / 2))
		val = haystack[mid]
		fmt.Println(val)
		if val == needle {
			return true
		} else if val > needle {
			high = mid
		} else if val < needle {
			low = mid + 1
		}
	}
	return false
}

func LinearSearch(haystack []int, needle int) bool {
	for _, v := range haystack {
		fmt.Println(v)
		if v == needle {
			return true
		}
	}
	return false
}

```