c | 声明结构体变量的三种方式

#include <stdio.h>

struct Student{//第一种
    int id;
    char *name;
    int age;
    float score;
};
typedef struct Student Student;

typedef struct teacher{//第二种    注：如果第16行已经写了teacher,则该行的teacher可写可不写
    
    char *name;
    int age;

}teacher;

struct Security_guard{//第三种
};

int main() {
    Student stu;
    teacher tea;
    struct Security_guard sec;//第三种定义方式：开头必须加上struct关键字
    return 0;
}