Binary search · 二分查找
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English
Binary search
The array is sorted. Return the index of target, or -1 if it isn't there. Binary search halves the range each step: check the middle element, then keep looking in just the left or right half. Far faster than scanning every element.
中文
二分查找
数组是已排序的。返回 target 的下标,如果不存在就返回 -1。二分查找每一步把范围减半:检查中间元素,然后只在左半或右半继续查找。比逐个扫描快得多。
Complete binarySearch(int[] a, int target) for a sorted array a: return the index of target, or -1 if absent. Use binary search. · 为已排序数组 a 完成 binarySearch(int[] a, int target):返回 target 的下标,不存在则返回 -1。使用二分查找。
Click Run to see the output here. · 点击“运行”查看此处输出。