Question

Fortran编程，本人在做abaqus进行热源模拟，现在想用Fortran编写程序用于调用，可是出现以下问题。求大神

总是出现：（本人编程方面一窍不通，希望给予详细指导）
Assertion failed: ( (last != 0) || (node == 0)) && (tree[last>>TREE_SHIFT][last&TREE_MASK].next == 0), file err_treelib.c, line 256

Answer 1

typedef struct lista{
struct lista *next;
int data;
}list;
void insert(list *h);
void del(list *h);

int main()
{
int flag;
list *head=(list *)malloc(sizeof(list));
head->next=NULL;
while(1)
{