feat(Go-Tool):2021/2/5: 新增二分查找区间内数值方法

This commit is contained in:
Huangzj
2021-02-05 14:47:59 +08:00
parent 5d9b7282ab
commit 75cba05f49
3 changed files with 89 additions and 0 deletions
+24
View File
@@ -26,3 +26,27 @@ func BinarySearch(list []int, value int) int {
return -1
}
//二分查找在两个数值之间的数据
func BinarySearchBetween(list []int, value int) int {
low := 0
high := len(list) - 1
var mid int
for low <= high {
//求mid
mid = (low + high) >> 1
//要算后面一个元素,所以下标要判断是否超过 并且需要考虑超过数组最大值的情况
if (mid+1 < len(list) && value > list[mid] && value < list[mid+1]) || value == list[mid] || (mid+1 >= len(list) && value > list[mid]) {
return mid
}
//位移
if value < list[mid] {
high = mid - 1
} else {
low = mid + 1
}
}
//未找到元素
return -1
}
+63
View File
@@ -40,3 +40,66 @@ func TestBinarySearch(t *testing.T) {
position = BinarySearch(oddNumList, -10)
fmt.Println(position)
}
func TestBinarySearchBetween(t *testing.T) {
evenNumList := []int{1, 2, 3, 5, 6, 7, 9, 10, 22, 111, 333, 431}
for _, r := range evenNumList {
position := BinarySearchBetween(evenNumList, r)
fmt.Println(position)
}
position := BinarySearchBetween(evenNumList, 999)
fmt.Println(position)
position = BinarySearchBetween(evenNumList, -10)
fmt.Println(position)
position = BinarySearchBetween(evenNumList, 1)
fmt.Println(position)
position = BinarySearchBetween(evenNumList, 3211)
fmt.Println(position)
position = BinarySearchBetween(evenNumList, 334)
fmt.Println(position)
position = BinarySearchBetween(evenNumList, 110)
fmt.Println(position)
position = BinarySearchBetween(evenNumList, 3222)
fmt.Println(position)
fmt.Println()
oddNumList := []int{1, 2, 3, 5, 6, 7, 9, 10, 22, 111, 333, 431, 3211}
for _, r := range oddNumList {
position := BinarySearchBetween(oddNumList, r)
fmt.Println(position)
}
fmt.Println("测试between")
fmt.Println()
position = BinarySearchBetween(oddNumList, 999)
fmt.Println(position)
position = BinarySearchBetween(oddNumList, -10)
fmt.Println(position)
position = BinarySearchBetween(oddNumList, 1)
fmt.Println(position)
position = BinarySearchBetween(oddNumList, 3211)
fmt.Println(position)
position = BinarySearchBetween(oddNumList, 334)
fmt.Println(position)
position = BinarySearchBetween(oddNumList, 110)
fmt.Println(position)
position = BinarySearchBetween(oddNumList, 3222)
fmt.Println(position)
}