I had written a program in C to implement a simple stack. But I am getting segmentation fault in my program and finding it hard to find out what is wrong. Can any one help,

```
   #include<stdio.h>
   #include<stdlib.h>
   struct stack_structure{
     int stack_array[10];
     int stack_pointer;
   };
   void push_into_stack(struct stack_structure *,int);
   int main(){
     int no = 8;
     struct stack_structure *st;
     st->stack_pointer = -1;
     push_into_stack(st,no);
     return 0;
   }
   void push_into_stack(struct stack_structure *s,int no){
     s -> stack_pointer++;
     s -> stack_array[s -> stack_pointer] = no;
   }

```