#include <stdio.h>
#include <stdlib.h>

struct node {
    int data;
    node* link;
};
struct node *head = NULL;
int main() 
{
    int n ;
    scanf("%d",&n);
    if(n<0) printf("Invalid input");
    else{
        struct node *temp ;
        temp = (struct node*)malloc(sizeof(struct node* temp));
        int i = 1;
        while(i<6){
            
            i++;
        }
    }
    return 0;
}