Programmer Think

Common string handling functions: String concatenation function: (strcat) char * strcat (char destination[], const char source[]); //Function: connect the string of parameter 2 to the end of the first parameter string //Return value: the first address of the first string //Note: ensure that the space length of parameter 1 is enough to store t ...

introduce In the process of learning C language, the processing of strings is very frequent, but C language itself has no string type, so we need to use functions to facilitate our processing of strings. ● find the length of the string         strlen ● string function with unlimited length         strcpy         strcat         strcmp ● ...

I like to specialize in the knowledge I love and the joy of completing the project come on. When your strength can't meet your goals, calm down and learn! Pointer Basic concept of pointer Function of pointer: memory can be accessed indirectly through pointer The memory number starts from 0 and is generally represented by hexadecimal d ...

Problem expression problem analysis The problem itself is easy to understand. Here are two solutions. The key to the problem of the linked list is to pay attention to the pointing between nodes. In addition, pay attention to each node, such as virtual head node, current node, previous node, next node, etc. the memory distribution of the li ...

Dictionary tree (prefix tree) summary: The dictionary tree (Trie) is used to determine whether a string exists or has a string prefix. Why do we need a dictionary tree to solve this kind of problem? If we have a dictionary that stores nearly 10000 words, even if we use hash, the actual cost of searching for a word in it is very lar ...

The meaning of smart pointer In C + +, new and delete are the keywords to apply for and destroy heap memory. After applying for heap memory, programmers often forget to delete to release heap memory, which is easy to cause a phenomenon - memory leakage, that is, a piece of heap memory is not released after being applied, so that other programs ...

subject Give you two strings s1 and s2 and write a function to determine whether s2 contains the arrangement of s1. In other words, one of the permutations of s1 is a substring of s2. Example 1: Input: s1 = "ab" s2 = "eidbaooo" Output: true Explanation: s2 contain s1 One of the permutations of ("ba"). Example 2: Input: s1= "ab" s2 = ...

Defining and using structure variables C language allows users to establish a combined data structure composed of different types of data, which is called structure Struct is the keyword that declares the structure type Declare the general form of a struct type: Struct structure name { Member table column } Declare each member: type name membe ...

I Why do I need a garbage collection mechanism When a Python program is running, it needs to open up a space in memory to store the temporary variables generated during running; After the calculation is completed, the result is output to the permanent memory. If the amount of data is too large and the memory space is mismanaged, it is easy to ...

preface Pointer is the key and difficult point of C language. Mastering pointer skillfully can better understand the storage mode of calculation, simplify the code and enhance the efficiency of the program. 1, Pointer overview A pointer is a variable that holds the address (number) of the memory unit. Pointer creation When defi ...