#include <stdio.h>
#include <stdlib.h>
struct cell{
  int data;
  struct cell *next;
};
struct slist{
  struct cell *head;
};

void construct_list(struct slist *);
void print_list(struct slist *);

int main(void)
{
  struct slist start;
  construct_list(&start);
  print_list(&start);
  return 0;
}

void construct_list(struct slist *start)
{
  struct cell *p;
  int i, y;
  p=start->head;
  for(i=0; i<6; i++){
    scanf("%d", &y);
    p=(struct cell *)malloc(sizeof(struct cell));
    p->data=y;
    p=p->next;
  }
}


void print_list(struct slist *start)
{
  struct cell *p;
  for(p=start->head; p!=NULL; p=p->next){
    printf("%d\n", p->data);
  }
}

Segmentation fault