这是我在逛 Stack Overflow 时遇见的一个高分问题:Why is processing a sorted array faster than an unsorted array?,我觉得这是一个非常好的用来讲分支预测(Branch Prediction)的例子,分享给大家看看 一、问题引入 先看这个代码: #include<algorithm>#include<ctime>#include<iostream>#include<stdint.h>intmain(...
You are the operator of a junction and you hear a train coming. You have no idea which way it will go. You stop the train to ask the captain which direction he wants. And then you set the switch appropriately. Trains are heavy and have a lot of inertia. So they take forever to st...
这是我在逛 Stack Overflow 时遇见的一个高分问题:Why is processing a sorted array faster than an unsorted array?,我觉得这是一个非常好的用来讲分支预测(Branch Prediction)的例子,分享给大家看看 一、问题引入 先看这个代码: #include <algorithm> #include <ctime> #include <iostream> #include <stdint....
In case of>comparison, in sorted array the branching behavior is very consistent: first, theifcondition is consistently false, then it is consistently true. This aligns very well with even the simplest branch prediction. In unsorted array the result of>condition is essentially random, thus thwarti...
Does a sorted array run faster than an unsorted array in Java?Brian L. Gorman
you can begin from the left and stop at 7 because that tells you that there won't be a 6 anywhere in the array (linear search). If the array wasn't sorted, you'd have to check every number in the array to make sure that there isn't a 6 hiding anywhere in the array...
Processing a sorted array can be faster than processing an unsorted array because certain algorithms and operations have a lower average time complexity when the input is already sorted. For example, the time complexity of the binary search algorithm is O(log n) for a sorted array...
Modifier and TypeMethod and Description int getIndex() Gets the values original position within its unsorted array. java.lang.String getValue() Gets the value that will be sorted. void setIndex(int withIndex) Sets the values original position within its unsorted array. void setValue...
排序arrayLists 、 我有一个场景,我有两个ArrayLists ArrayList<String> sortedArrayList ArrayList<String> unSortedArrayList 我必须根据sortedArrayList对unSortedArrayList进行排序。也就是说,sortedArrayList已经排序了,现在基于sortedArrayList,我必须对unSortedArrayList排序。 unSortedArrayList size is <= to the size of...
(a,b)=>a-b)array=SortedArray.parse([4,2,3,4],(a,b)=>a-b)// throws UnsortedArrayError// "SortedArray.unsafe" does not verify the array is actually sorted.// Use when performance is critical and one can assume the array is sorted.array=SortedArray.unsafe([4,2,3,4],(a,b)=...