Searching for an element in a sorted array using a binary algorithm

Given an array of integers sorted in ascending order. Write a binary search function that returns the position of the sought value, and if the value is absent — returns -1.

package main

import "fmt"

func main() {
    data := []int{1, 2, 5, 10, 100}
    // implement binary search here
    fmt.Println(data)
}