1.) #include<stdio.h> 2.) #include<malloc.h> 3.) struct node 4.) { 5.) int val; 6.) struct node *next; 7.) }; 8.) typedef struct node *Node; 9.) struct stack 10.) { 11.) Node head; 12.) }; 13.) typedef struct stack *Stack; 14.) int main() 15.) { 16.) Stack s; 17.) int val; 18.) s->head=NULL; 19.) return 0; 20.) } Note: line numbers are provided for easy discussion abt the line Buddies....This program gives me segmentation fault but when i interchanged line 16 and 17 it worked fine.. I dont know wat actually happened.somebody plzz help me....thanks in advance