43 lines
1.4 KiB
Kotlin
43 lines
1.4 KiB
Kotlin
|
||
// （版本二）左闭右闭区间
|
||
class Solution {
|
||
fun search(nums: IntArray, target: Int): Int {
|
||
var left = 0
|
||
var right = nums.size - 1 // [left,right] 右侧为闭区间，right 设置为 nums.size - 1
|
||
while (left <= right) {
|
||
val mid = (left + right) / 2
|
||
if (nums[mid] < target) left = mid + 1
|
||
else if (nums[mid] > target) right = mid - 1 // 代码的核心，循环中 right 是闭区间，这里也应是闭区间
|
||
else return mid
|
||
}
|
||
return -1 // 没有找到 target ，返回 -1
|
||
}
|
||
}
|
||
|
||
class Solution_2 {
|
||
|
||
fun search(nums: IntArray, target: Int): Int {
|
||
var left = 0
|
||
var right = nums.size // [left,right) 右侧为开区间，
|
||
while (left < right) {
|
||
val mid = (left + right) / 2
|
||
if (nums[mid] < target) left = mid + 1
|
||
else if (nums[mid] > target) right = mid // 代码的核心，循环中 right 是开区间，这里应是开区间
|
||
else return mid
|
||
}
|
||
return -1 // 没有找到 target ，返回 -1
|
||
}
|
||
}
|
||
|
||
// 测试用例
|
||
fun main() {
|
||
val nums = intArrayOf( 0, 1, 2, 4, 5, 6, 7)
|
||
val target = 0
|
||
val solution = Solution()
|
||
val result = solution.search(nums, target)
|
||
val solution2 = Solution_2()
|
||
val result2 = solution2.search(nums, target)
|
||
println("Solution 1: $result") // 0
|
||
println("Solution 2: $result2") // 0
|
||
|
||
} |