structure

问题 I am writing a C code to find the middle of linked list. I understood the logic but was unable to figure out how pointers are being used. What is the difference in the way Node *head and Node** head_ref work? void middle(struct Node *head) ; void push(struct Node** head_ref, int new_data) ; 回答1: In the first function header, *head is a pointer to a node object which is allocated somewhere in memory: void middle(struct Node *head); _____________________ | | *head --> | Node object | | [val=1][

问题 Below I have a snippet of code that I am using to create a structure with field names that are defined in the array 'field_names'. This seems like a very clunky way of creating the structure. Is there a better way that I can do this in one line? Perhaps there is some syntax trick to help me avoid the for loop? %array of names to create field names from field_names = ['num1', 'num2', 'num3', 'etc']; data = struct() for i = 1:length(field_names) data.field_names(i) = rand() %some random value,

问题 Hey I'm having trouble understanding on how structs get passed to functions as pointers because i want to modify my structs later in my project. So I'm creating a game that has rooms and this function creates a 2d array of the world. I'm passing in struct room and struct World because I'm storing each room in a cord in World struct which is a 2d array. When i got print out each room, it doesn't print anything out and i think the problem is with my pointers. So my first function that's in a

问题 I want to create a directory structure table as described in this question where: Directory = "Primary Key" id field, typically an integer Directory_Parent = "Foreign Key" id field, which points to the id of another Directory in the same table Value = string containing the directory/folder name Given Tree/Fruit/Apples/ Directory | Directory_Parent | Value 0 null Root 1 0 Tree 2 1 Fruit 3 2 Apples A Root folder has been created at Primary Key 0 with a null parent. My paths are being imported

问题 I have the following structures. typedef struct arr_integer { int size; int *arr; }arr_arr_integer; arr_arr_integer alloc_arr_integer(int len) { arr_arr_integer a = {len, len > 0 ? malloc(sizeof(int) * len) : NULL}; return a; } What I intend to do is fill the matrix with the above structures. But I don't know how to manipulate the structure to fill the matrix. Tried it this way, but I get an error. int main(int argc, char const *argv[]) { int len,rows,columns; scanf("%d",&rows); scanf("%d",

问题 I have to write a function that sorts structs in an array. the struct is: #define MAX_USERNAME_LENGTH 16 typedef struct{ char username[MAX_USERNAME_LENGTH]; unsigned int rides; unsigned int rank; } driver; The program load the data from a .txt file and fills an array driver driver_list[256] I have to sort driver_list by ranks AND number of rides. So if my file contains //user rides rank frank209 3 6 john76 7 6 harry99 2 2 bob77 5 2 Output must show: john76 7 6 frank209 3 6 bob77 5 2 harry99 2

问题 I have to build a nested structure to store some basic information about some person (name, age, address). So I created a structure called "info" and to hold the address I created another nested structure inside "info" called "address". But whenever I prompt to store the values using a for loop, I get errors. What is the problem here and how can I solve it? [Error] 'struct Info' has no member named 'address' [Warning] declaration does not declare anything [enabled by default] #include <stdio

问题 I wanna create nested entity with DIH using SOLR 6.x i read Defining nested entities in Solr Data Import Handler and jira https://issues.apache.org/jira/browse/SOLR-5147 what i did Schema.xml <fields> <field name="variantList" type="string" indexed="true" stored="true" /> <field name="variantList.variants" type="string" multiValued="false" required="false"/> <field name="variantList.stockMinimum" type="int" multiValued="false" required="false"/> <field name="variantList.stockOnHand" type="int

问题 I am currently working on an assignment and was curious what this warning is when compiling and how to remedy it. It will build but when I debug it will get an error screen. Below is the warning that comes up. 1>c:\users\cesteves\documents\c programming\inventory\inventory\inventory.cpp(48): warning C4473: 'scanf_s' : not enough arguments passed for format string note: placeholders and their parameters expect 2 variadic arguments, but 1 were provided note: the missing variadic argument 2 is

问题 sorry for the long and confusing title, but I couldn't think of a better way to ask this. So, what I have is a class: template <typename T> class Set { public: //random member functions here private: struct Node{ T key; Node *right; Node *left; int height; }; public: Node* r_add(Node *temp); }; Node* Set<T>::r_add(Node *temp) { return temp; } When I try to implement the function r_add, I keep getting the error that the return type of out-of-line definition differs from that in the declaration