1. 正向查找

      1. func searchInsert(nums []int, target int) int {
      2.  for i, num := range nums {
      3.      if num >= target {
      4.          return i
      5.      }
      6.  }
      8.  return len(nums)
      9. }

    2. 二分查找

      func searchInsert(nums []int, target int) int {
 if len(nums) == 0 {
     return 0
 }

 l := 0
 h := len(nums)
 mid := 0

 for l < h {
     mid = l + (h - l) / 2
     num := nums[mid]

     if num > target {
         h = mid
     } else if num < target {
         l = mid + 1
     } else {
         break
     }
 }

 return l + (h - l) / 2
}