C 无法访问数组

Question

我正在编写一个列出学生并添加学生的C程序，但是当我添加一个新学生时，虽然我可以成功读取该值，但该函数只能将前2个元素打印到屏幕上，而无法正确读取新添加的元素.

代码在这里：

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

typedef char str[50];

typedef struct{
    str name;
    str surname;
    int year;
    int no;
}Student;

void list(Student[2],int sn);

int main() {
    Student students[100] = {
        {"samuel","any",20,111},
        {"veronica","suqal",25,87}
    };

    int sl = 2;

    puts("list, add, exit");
    puts("------------------------\n"); 

    str process;

    while(strcmp(process,"exit")) {

        gets(process);

        if(!strcmp(process,"list")) list(students,sl);
        else 
        if(!strcmp(process,"add")) { 

            sl++;

            str name,surname,year,no;

            printf("\n name: ");
            gets(name);

            printf("\n surname: ");
            gets(surname);

            printf("\n year: ");
            gets(year);
            
            printf("\n no: ");
            gets(no); 


            strcpy(students[sl].name,name);
            strcpy(students[sl].surname,surname);
            students[sl].no = atoi(no);
            students[sl].year = atoi(year);

            printf("%s %d",name,atoi(no));


        } else if(!strcmp(process,"exit")) { 
            puts("-------exiting--------");

        } 
        
        else
        {
            str out = "not known command: ";
            strcat(out,process);
            puts(out);
        }
    }
    return 0;
};

void list(Student* students,int sn) {
    for(int i=0;i<sn;i++) 
    { 
        Student std = students[i];
        printf("student: \n name: %s, surname: %s, years: %d, no: %d \n",std.name,std.surname,std.year,std.no);
    }
};

当我添加一个新元素时，我可以使用 printf 在屏幕上读取它，但是当我使用函数列出它时，会发生这种情况：

list, add, exit
------------------------

add

 name: hello

 surname: world

 year: 1

 no: 1
hello 1

list
student:
 name: samuel, surname: any, years: 20, no: 111
student:
 name: veronica, surname: suqal, years: 25, no: 87
student:
 name: , surname: , years: 0, no: 0

Answer 1

您应该在存储数据后立即增加“sl”。 这里，当你想添加第三个学生，但访问时，sl 等于 3 array[3] 给出数组的第四个值。