c - 当我运行这个程序时结构崩溃

Question

我正在练习 C，我正在尝试创建一个包含多个元素的结构体，并循环遍历并打印出结构体中的所有数据。然而，当我运行这个程序时，我遇到了段错误。我有点困惑为什么会发生这种情况，因为我能够在没有任何警告或失败的情况下编译它，并且程序运行它最后也会崩溃。

这是我运行程序时的输出:

lnx-v1:242> ./multiArrayStruct
     Records of EMPLOYEE : 1
 Id is: 1
 First name is: Joe
 Last name is: Johnson
 Employee age is 25
     Records of EMPLOYEE : 2
 Id is: 2
 First name is: Kyle
 Last name is: Korver
 Employee age is 25
     Records of EMPLOYEE : 3
 Id is: 3
 First name is: Adam
 Last name is: Thompson
 Employee age is 25
 Segmentation fault (core dumped) <-------why is this crashing ? 

这也是我的代码:

#include <stdio.h>
#include <string.h>

struct employee 
{
    int empId;
    char empNameFirstName[20];
    char empNameLastName[20];
    int empAge;

};



int main() 
{
        struct employee record[2];

        // First employee record 
        record[0].empId=1;
        strcpy(record[0].empNameFirstName, "Joe");
        strcpy(record[0].empNameLastName, "Johnson");
        record[0].empAge=25;

        // second employee record 
        record[1].empId=2;
        strcpy(record[1].empNameFirstName, "Kyle");
        strcpy(record[1].empNameLastName, "Korver");
        record[1].empAge=25;

        // third employee record 
        record[2].empId=3;
        strcpy(record[2].empNameFirstName, "Adam");
        strcpy(record[2].empNameLastName, "Thompson");
        record[2].empAge=25;

        for(int i = 0; i < 3;i++)
        {
            printf("     Records of EMPLOYEE : %d \n", i+1);
            printf(" Id is: %d \n", record[i].empId);
            printf(" First name is: %s \n", record[i].empNameFirstName);
            printf(" Last name is: %s \n", record[i].empNameLastName);
            printf(" Employee age is %d\n", record[i].empAge);

        }

        return 0;
}

Answer 1

您创建一个包含 2 个元素的数组:

    struct employee record[2];
                           ^----

实际上是record[0]和record[1]。但随后您尝试分配给未定义的第三个元素:

    record[2].empId=3;
           ^---

这意味着您正在未分配/未定义的内存空间中乱写。