The Code Gallery

Step 1: If TOP >= SIZE – 1 then
               Write “Stack is Overflow”
Step 2: TOP = TOP + 1
Step 3: STACK [TOP] = X

Step 1: If TOP = -1 then
             Write “Stack is Underflow”
Step 2: Return STACK [TOP]
Step 3: TOP = TOP - 1

#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
#define SIZE 5
void push(int *STACK,int x);
void pop(int *a);
void display(int *a);
int TOP=-1;
int STACK[SIZE];
void main()
{
      int x,ch;
      clrscr();
      while(1)
      {
          printf("Select Your Choice:\n");
          printf("(1) PUSH\n");
          printf("(2) POP\n");
          printf("(3) Display\n");
          printf("Enter Your Choice\n");
          scanf("%d",&ch);
          switch(ch)
          {
              case 1:
                   printf("Enter Element:");
                   scanf("%d",&x);
                   push(STACK,x);
                   break;
              case 2:
                   pop(STACK);
                    break;
              case 3:
                   display(STACK);
                   break;
              case 4:
                   exit(0);
          }
}
}
void push(int *STACK,int x)
{
      if(TOP>=SIZE-1)
      printf("Stack is Overflow");
      else
      {
          TOP=TOP+1;
          STACK[TOP]=x;
      }
}
void pop(int *STACK)
{
      int x;
      if(TOP==-1)
      printf("Stack is Underflow");
      else
      {
          printf("Deleted Element is %d\n",STACK[TOP]);
          TOP=TOP-1;
      }
}
void display(int *STACK)
{
      int i;
      if(TOP==-1)
      printf("Stack is Empty\n");
      else
      {
          for(i=TOP;i>=0;i--)
          printf("%d\n",STACK[i]);
      }
}