Hacktoberfest 2026:维护者为十月标记出来的 issue,仍然开放、适合新手。 浏览 Hacktoberfest issue

malloc memory for an array of structure in c

未关闭
#30 0 条评论 0 个 reaction 已指派 0 人 在 GitHub 查看

还没有人认领这个 Issue。

评估

难度
2/5
预计耗时
1-3 小时
新手友好度
35/100
Issue 类型
文档
描述清晰度
需要澄清
活跃度
停滞
技术栈
c
领域
documentation

调研方向

Start with the issue's linked DelftStack article and supplied C example. Determine how this repository organizes programming tips, then add the malloc-based array-of-struct example with its explanation and output in the appropriate format. Done means the tip is included and readable in the repository.

由索引模型根据 Issue 内容生成。

描述

Create an Array of struct Using the malloc() Function in C
There is another way to make an array of struct in C. The memory can be allocated using the malloc() function for an array of struct. This is called dynamic memory allocation.
The malloc() (memory allocation) function is used to dynamically allocate a single block of memory with the specified size. This function returns a pointer of type void.

The returned pointer can be cast into a pointer of any form. It initializes each block with the default garbage value.

The syntax of malloc() function is as below:

ptrVariable = (cast-type*) malloc(byte-size)
The complete program to create an array of struct dynamically is as below.

#include<stdio.h>
int main(int argc, char** argv)
{
    typedef struct
    {
        char* firstName;
        char* lastName;
        int rollNumber;

    } STUDENT;

    int numStudents=2;
    int x;
    STUDENT* students = malloc(numStudents * sizeof *students);
   
    for (x = 0; x < numStudents; x++)
    {
        students[x].firstName=(char*)malloc(sizeof(char*));
       
        printf("Enter first name :");
        scanf("%s",students[x].firstName);
        students[x].lastName=(char*)malloc(sizeof(char*));
        printf("Enter last name :");
        scanf("%s",students[x].lastName);
        printf("Enter roll number  :");
        scanf("%d",&students[x].rollNumber);

    }

    for (x = 0; x < numStudents; x++)
        printf("First Name: %s, Last Name: %s, Roll number: %d\n",students[x].firstName,students[x].lastName,students[x].rollNumber);

    return (0);
}

Output:

Enter first name:John
Enter last name: Williams
Enter roll number:1

Enter first name:Jenny
Enter last name: Thomas
Enter roll number:2

First Name: John Last Name: Williams Roll Number:1
First Name: Jenny Last Name: Thomas Roll Number:2

主要语言
Python
星标
5
派生
2
PR 合并指标
30 天内没有已合并 PR

环境准备

这个项目没有提供开发容器、Dockerfile 或贡献指南,环境需要你自己搭建:先看它的 README,通用步骤见我们的新手贡献指南。

从这里开始

  1. 先读完整个 Issue,再读项目的贡献指南。
  2. 在 Issue 下留言说明你要接手 —— 这能避免两个人做同样的事。
  3. Fork 仓库,在一个分支上完成修改。
  4. 提交 Pull Request,并在描述里引用这个 Issue 编号。

davideuler/programming-tips 的其他 Issue

查看 davideuler/programming-tips 的全部 Issue

相似的 Issue

更多 Python Issue

把新 issue 发到你的邮箱

精选适合新手参与的 GitHub issue 摘要。