// editor1
#include<stdio.h>
#include<stdlib.h>
#include<ctype.h>
struct node
{
    float data;
    struct node*next;
}*head=NULL,*tail;
int main()
{
    int n,flag=0;
    if(scanf("%d",&n)!=1)
    {
       printf("Invalid input ");
       return 0;
    }
    if((n<=0)||(n>1000))
    {
    if(n==0)
    {
        float f;
        if(scanf("%f",&f)!=1)
        {
            printf("Invalid input");
            return 0;
        }
        struct node*newnode=(struct node*)malloc(sizeof(struct node));
        newnode->
     }
    }
}