Simple binary search on a slice (array) in Go (GoLang).

binarysearch.go

package slice

// BinarySearch searches a `target` value in `nums`
// using the "binary search" algorithm.
// It returns its position if found or -1 if not found.
func BinarySearch(nums []int, target int) int {
    if len(nums) == 0 {
        return -1
    }

    for left, right := 0, len(nums)-1; left <= right; {
        pos := left + (right - left) / 2
        val := nums[pos]
        if val == target {
            return pos
        } else if val < target {
            left = pos + 1
        } else /* if val > target */ {
            right = pos - 1
        }
    }
    return -1
}