C经典 结构图初始化三种方式

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main(int argc, const char * argv[])
{

    //1
    struct Student{
        int age;
        int grade;
        char name[21];
    }stu;

    stu.age = 20;
    stu.grade = 3;
    strcpy(stu.name, "占上风");

    printf("%s\n",stu.name);
    printf("%ld\n",sizeof(stu.name));//=21,值得是空间
    // utf-8 一个汉字占三个字节
    printf("%ld\n",strlen(stu.name));//=9

    printf("\n\n");
    //-2----------
    struct Student stu2 = {22,3,"lishi"};
    printf("%s\n",stu2.name);
    printf("%ld\n",sizeof(stu2.name));//=21,值得是空间
    // 
    printf("%ld\n",strlen(stu2.name)); // 5
    printf("\n\n");

    //-3----
    struct Student stu3 ={.name = "gogo"};
    printf("%s\n",stu3.name);
    return 0;
}