70 lines
1.9 KiB
Kotlin
70 lines
1.9 KiB
Kotlin
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/*
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* This Kotlin source file was generated by the Gradle 'init' task.
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*/
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package binarySearch
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class Solution {
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fun search(nums: IntArray, target: Int): Int {
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var left = 0
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var right = nums.size - 1 // [left,right] 右侧为闭区间，right 设置为 nums.size - 1
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while (left <= right) {
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val mid = (left + right) / 2
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if (nums[mid] < target) left = mid + 1
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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
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else return mid
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}
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return -1 // 没有找到 target ，返回 -1
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}
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}
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// 测试用例
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fun main() {
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val nums = intArrayOf(0, 1, 2, 3, 4, 5, 6, 7, 8)
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println("请输入要查找的数字:")
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val input = readLine()
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// 验证输入有效性
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if (input.isNullOrBlank()) {
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println("错误：未输入任何内容")
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return
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}
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val target = input.toIntOrNull() ?: run {
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println("错误：请输入有效的整数")
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return
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}
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val solution = Solution()
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val result = solution.search(nums, target)
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if (result == -1){
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println("不存在$target")
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}
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else{
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println("目标索引位置: $result")
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}
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}
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// fun main() {
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// val nums = intArrayOf(4, 5, 6, 7, 0, 1, 2)
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// val reader = System.`in`.bufferedReader()
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// print("请输入要查找的数字: ")
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// System.out.flush()
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// val input = reader.readLine()
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// if (input.isNullOrBlank()) {
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// println("错误：未输入任何内容")
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// return
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// }
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// val target = input.toIntOrNull() ?: run {
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// println("错误：请输入有效的整数")
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// return
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// }
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// val solution = Solution()
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// val result = solution.search(nums, target)
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// println("目标索引位置: $result")
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// }
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