Programmer Think

Foreword: making A, B, D and C has been timeout, and I didn't think of how to optimize it. Rating: 1153 + 146 -- > 1299 (green) Don't talk about the problem, just talk about the solution and code. A. Red and Blue Beans   topic type: greed    analysis: if r is less than B, try to replace 1 with more, so calculate the differenc ...

Example: consecutive interval number Xiao Ming has been thinking about such a strange and interesting question these days: How many consecutive intervals are there in an arrangement of 1 ∼ N? The definition of the serial interval here is: If all the elements in the interval [L,R] (i.e. the L-th to r-th elements of this arrangement) can ...

There are many data structures in the camera HAL layer. When looking at the code, we often look for a long time to understand these data structures. In order to facilitate everyone's study, we specially summarize some data structures and their locations: 1.hardware/libhardware/include/hardware/camera_common.h: 1.1 camera_info_t : camera_info ...

T1: sequence query This question can be queried up to 10000 times. If recursion is used only, there will be multiple repeated calculations. Therefore, an array can be used to store the results calculated in the recursion process. When querying f(i), if f(i) has been calculated before, it can be output directly; If it has not been calculated, ...

Introduction and use of stack stack is a container adapter, which is specially used in the context of last in first out operation. Its deletion can only insert and extract elements from one end of the container.Stack is implemented as a container adapter. A container adapter encapsulates a specific class as its underlying container, and pr ...

Why use concurrenthashmap (the disadvantage of HashMap) HashMap is the most commonly used Map class in Java. It has good performance and fast speed, but it can not guarantee thread safety. It can use null value as Key/value The thread insecurity of HashMap is mainly reflected in the dead loop when resizing and fast fail when using iterator In ...

Recursively generate binary reflection Code: Requirements: We use recursion to generate binary reflection gray code. What is gray code? The typical Binary Gray Code is abbreviated as gray code, which is named after the patent "Pulse Code Communication" of Frank Gray (18870913-19690523) published in 1953. It was originally used to ...

Meaning: let n ants to an apple tree, and give the corresponding coordinates of N ants and N apple trees. To calculate the weight is to calculate the distance between coordinate points, and it is required to calculate the minimum distance! Idea: use the maximum weight perfect matching problem, but now the problem is to find the minimum weight. ...

[Title 81] Title: a company uses a public telephone to transmit data. The data is a four digit integer and is encrypted in the transmission process. The encryption rules are as follows: add 5 to each number, then replace the number with the remainder of sum divided by 10, and then exchange the first and fourth bits, and the second and third bi ...

1. Basic introduction Huffman tree, alias "Huffman tree", "Huffman tree", "optimal tree" and "optimal binary tree" Given n weights as n leaf nodes, a binary tree is constructed. If the weighted path length (wpl) of the tree reaches the minimum, such a binary tree is called the optimal binary tree, also ...