Page 163 - DCAP201_FUNDAMENTALS_OF_DATA_STRUCTURES

Fundamentals of Data Structures

Notes //Deleting an element from the stack.
int pop(struct stack *st)
{
int num;
if(st->top == -1)
{
printf("nStack underflow(i.e., stack empty).");
return NULL;
}
num = st->arr[st->top];
st->top--;
return num;
}
void display(struct stack *st)
{
int i;
for(i=st->top;i>=0;i--)
printf("n%d",st->arr[i]);
}
int main()
{
int element,opt,val;
struct stack ptr;
init_stk(&ptr);
printf("nEnter Stack Size :");
scanf("%d",&size);
while(1)
{
printf("nntSTACK PRIMITIVE OPERATIONS");
printf("n1.PUSH");
printf("n2.POP");
printf("n3.DISPLAY");
printf("n4.QUIT");
printf("n");
printf("nEnter your option : ");
scanf("%d",&opt);
switch(opt)
{
case 1:
printf("nEnter the element into stack:");
scanf("%d",&val);

Contd...

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