Programmer Think

Topic introduction Question 215: https://leetcode-cn.com/problems/kth-largest-element-in-an-array/ The kth largest element was found in an unordered array. Note that you need to find the k-th element of the array instead of the largest element. analysis To find the k-largest element in the array, the first thing you can think of is, of cou ...

Large top heap: Based on the complete binary tree, the value of each node is greater than or equal to the value of its left and right child nodes p moves forward through the loop p -- pointer in the main function public static void main(String[] args) { int[] arr = {8,7,3,5,4,9,1,3}; for (int p = arr.length-1;p>=0;p--){ ...

Title Link: Turing Tree General meaning There is a sequence of length n, numbered from 1 to n, and each position has an element value Query: multiple queries, the sum of elements after de duplication in each query [l, r] Problem solving ideas Offline query + segment tree / tree array or chairman tree Acacia topic recommendation Solution ...

3.1 sparse array 3.1.1 first look at a demand The Gobang program has the functions of saving, exiting and continuing the upper board. Analyze the problem: Because many values of two-dimensional array are the default value of 0, many meaningless data = = > sparse array are recorded. 3.1.2 basic introduction When most elements in an array ...

Say at the beginning This blog only provides learning materials and my personal review. In the process of learning algorithms, the code should be typed by myself. It is not convenient to copy and paste the code directly. Copy code without harm. preface The original intention of writing this series of blogs is that the process of learning alg ...

background One day, a group of dogs suddenly began to moisten people in the past, so the students banned this part of the science and technology building.   ~   Deadcodes: old machine room Problem surface Your country ...

A references Book "sword finger offer (Second Edition)" Search in JZ01 binary array 1. Title Description In a two-dimensional array (each one-dimensional array has the same length), each row is sorted in ascending order from left to right, and each column is sorted in ascending order from top to bottom. Please complete a function, ...

acwing game 24 This week's competition has three topics: simulation, enumeration and simulation acwing 4070. XOR Link: 4070. XOR - AcWing question bank Title Description Problem solving ideas Very simple simulation, record the maximum value and the last input when entering, and don't even open the array code #include<iostream> ...

Understanding time complexity: Constant time operation: if an operation has nothing to do with the amount of data, it is completed within a fixed time every time, which is called constant operation. Time complexity is an indicator of the number of constant operations in an algorithm flow. It is often represented by 0 (pronounced big0). S ...

2022 Niuke winter vacation algorithm basic training camp 4 A-R Title Description: Xiao Hong gets a string of length n, which is only composed of uppercase letters. Xiao Hong likes red very much (indicated by the letter 'R'), but she hates purple very much (indicated by the letter 'P'). She wants to take a continuous substring that conta ...