3. Stack-Operation.c

#include<stdio.h>
#include<stdlib.h>
#define MAX 10

int stack[MAX], top=-1 ;

void push(){
   int item;
   if (top==MAX-1){
      printf("Stack Overflow!\n");
  }
   else{
     printf("Enter the element to be pushed into the stacks :");
     scanf("%d",&item);
     top++;
   stack[top]=item;
  } 
}

void pop(){
    if(top==-1){
        printf("Stack Underflow!\n");
    }
    else{
        printf("Popped element is %d\n",stack[top]);
        top--;
    }
}

void isPallindrome(){
    int flag=1,i;
    printf("Stack Contents are :\n");
      for(i=top;i>=0;i--)
        printf("|%d|\n",stack[i]);

    printf("Reverse of stack contents are:\n");
      for(i=0;i<=top;i++)
        printf("|%d|\n",stack[i]);
    for(i=0;i<=top/2;i++)
    {
        if(stack[i]!=stack[top-i]){
            flag=0;
            break;
        }
    }
    if(flag==1){
        printf("It is Pallindrome number\n");
    }
    else{
        printf("It is not Pallindrome\n");
    }
}

void display(){
    int i;
    if(top==-1){
        printf("\nStack Underflow!");
    }
    else {
    for(i=top;i>=0;i--){
        printf("%d\n",stack[i]);
    }
  }
}

int main(){
    int ch,elem;
    while(1){
        printf("STACK OPERATION\n");
        printf("1.Push\n");
        printf("2.Pop\n");
        printf("3.Pallindrome\n");
        printf("4.Display\n");
        printf("5.Exit\n");
        printf("Enter your choice:");
        scanf("%d",&ch);
        switch (ch)
        {
            case 1:push(); break;
            case 2:pop();break;
            case 3:isPallindrome();break;
            case 4:display();break;
            case 5:exit(0);break;
            default: printf("Invalid Choice\n");break;
        }
    }
    return 0;
}