我有一個具有多個結構的數組。當我要求用戶在第一次輸入數據時一切正常,但是當我再次詢問數組中的下一個位置時,程序崩潰。如果這種方法不起作用,那麼開始時程序不會崩潰? malloc有問題嗎?程序結構數組崩潰
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct student {
char name[50];
int semester;
};
struct prof {
char name[50];
char course[50];
};
struct student_or_prof {
int flag;
int size;
int head;
union {
struct student student;
struct prof prof;
}
}exp1;
struct student_or_prof *stack;
void init(int n)
{
stack = malloc(n);
}
int push(struct student_or_prof **pinx,int *head,int n)
{
char name[50];
printf("\nn= %d\n",n);
printf("\nhead= %d\n",*head);
if(*head==n)
{
printf("Stack is full.\n");
return 1;
}
char x;
printf("Student or Professor? [s/p] ");
getchar() != '\n';
scanf("%c",&x);
if(x=='s')
{
getchar() != '\n';
pinx[*head]->flag = 0;
printf("\n\nGive student's name: ");
fgets(pinx[*head]->student.name,sizeof(pinx[*head]->student.name),stdin);
printf("\nGive student's semester: ");
scanf("%d",&(pinx[*head]->student.semester));
printf("\nName = %s\tSemester = %d",pinx[*head]->student.name,pinx[*head]->student.semester);
}
else if(x=='p')
{
getchar() != '\n';
pinx[*head]->flag = 1;
printf("\n\nGive professor's name: ");
fgets(pinx[*head]->prof.name,sizeof(pinx[*head]->prof.name),stdin);
printf("\nGive course: ");
fgets(pinx[*head]->prof.course,sizeof(pinx[*head]->prof.course),stdin);
printf("\nName = %s\tCourse = %s\n",pinx[*head]->prof.name,pinx[*head]->prof.course);
}
(*head)++;
printf("\nhead= %d\n",*head);
}
int main()
{
int n,i;
printf("Give size: ");
scanf("%d",&n);
init(n);
for(i=0;i<n;i++)
push(&stack,&exp1.head,n);
return 0;
}
你覺得有多少'student_or_prof' *節點*可以放入分配了* this *的內存中?'stack = malloc(n);'? – WhozCraig