Java UpperBound
/** * <html> * <body> * <P> Copyright 1994-2018 JasonInternational </p> * <p> All rights reserved.</p> * <p> Created on 2018年4月10日 上午9:46:32</p> * <p> Created by Jason</p> * </body> * </html> */ package cn.ucaner.algorithm.search; /** * Upper bound search algorithm.<br> * Upper bound is kind of binary search algorithm but:<br> * -It returns index of first element which is grater than searched value.<br> * -If searched element is bigger than any array element function returns first index after last element.<br> * <br> * Behaviour for unsorted arrays is unspecified. * <p> * Complexity O(log n). * <br> * @author Bartlomiej Drozd <[email protected]> * @author Justin Wetherell <[email protected]> */ public class UpperBound { private UpperBound() { } public static int upperBound(int[] array, int length, int value) { int low = 0; int high = length; while (low < high) { final int mid = (low + high) / 2; if (value >= array[mid]) { low = mid + 1; } else { high = mid; } } return low; } }