Stack array implementation

#include<stdio.h>
#define max 5
int stack[max+1]={0,0,0,0,0,0};
int top=0;

void push()
{
    if(top==max) printf("\nStack Overflow\n");
    else-{
        int num;
        printf("Enter the number: ");
        scanf("%d",&num);
        top++;
        stack[top]=num;
    }
}

void pop()
{
    if(top==0) printf("\nUnderflow\n");
    else
    {
        int item;
        item=stack[top];
        stack[top]=0;
        top--;
        printf("The deleted item is: %d\n",item);
    }
}

void display()
{
    int i;
    printf("\nThe stack is:\n");
    for(i=max;i>0;i--)
    {
        printf("%d\n",stack[i]);
    }
    printf("\n");
}

int main()
{
    int x;
    while(1)
    {
        printf("Press 1 to insert element\n");
        printf("Press 2 to remove element\n");
        scanf("%d",&x);
        if(x==1) push();
        else if(x==2) pop();
        display();
    }
}