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The computeIfAbsent(Key, Function) method of HashMap class is used to compute value for a given key using the given mapping function, if key is not already associated with a value (or is mapped to null) and enter that computed value in Hashmap else null. If mapping function of this method returns null, then no mapping …
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The edit distance algorithm is very popular among the data scientists. It’s one of the basic algorithms used for evaluation of machine translation and speech recognition. The naive approach would be to check for all possible edit sequences and choose the shortest one in-between. That would result in an exponential complexity and it’s an overkill …
Principle of Network Application Application Architecture Client-Server Architecture Data Center, housing a large number of hosts Google, Amazon, etc. P2P Architecture Peers. Application exploits direct communication between pairs of intermittently connected hosts. Traffic-intensive applications: BitTorrent, XunLei, etc. Processing Communicating Processes communicate among different end-system hosts Processes on two different end systems communicate with each other …
Continue reading “Application Layer – Reading Notes on Computer Networking A Top-Down Approach Ch.2”
Long is the Object form of long, and Integer is the object form of int. Integer is a signed 32 bit integer type Denoted as Int Size = 32 bits (4byte) Can hold integers of range -2,147,483,648 to 2,147,483,647 default value is 0 Long is a signed 64 bit integer type Denoted as Long Size …
For example, if here are one BST as: [Integer.MIN_VALUE, Integer.MIN_VALUE] If I want to compare if the left child node is smaller or equal to parent nod – 1, the value gonna be overflow. In this case, don’t use Integer.MIN_VALUE, use null as the default instead. Here is an example about using null as comparison …
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I have moved pictures to drawable folder: But when I tried to use one of the as the background picture, I can’t find some of them: The reason is: Please Note the image name can only include lowercase a-z, 0-9, or underscore, otherwise there will have an error when you rebuild the android project. The …
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From JavaDoc for Stack, we could see: "A more complete and consistent set of LIFO stack operations is provided by the Deque interface and its implementations, which should be used in preference to this class. For example:" Deque<Integer> stack = new ArrayDeque<>(); Here are some answers from Why should I use Deque over Stack?. Inconsistency: …
This is No.99 in LeetCode. Here are approaches to this problem: Approach 1: Sort an Almost Sorted Array Where Two Elements Are Swapped Algorithm Here is the algorithm: Construct inorder traversal of the tree. It should be an almost sorted list where only two elements are swapped. Identify two swapped elements x and y in …
Let’s use the Math.random method to generate a random number in a given range: public int getRandomNumber(int min, int max) { return (int) ((Math.random() * (max – min)) + min); } Why does that work? Well, let’s look at what happens when Math.random returns 0.0, it’s the lowest possible output: 0.0 * (max – min) …
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