704. 二分查找

func search(nums []int, target int) int {
    left := 0
    right := len(nums)-1

    for left <= right {
        mid := (left+right)/2
        if target > nums[mid] {
            left = mid+1
        } else if target < nums[mid] {
            right = mid-1
        } else {
            return mid
        }
    }
    return -1
}