#include<stdio.h>
int main()
{
    int n;
    scanf("%d" , &n);
    if(n<=1)
    {
        printf("Invalid input\n");
        return 0;
        
    }
    int ids[n],dup[100],dcount=0;
    for (int i=0;i<n;i++){
     for(int j=i+1;j<n;j++){
         if(ids[i]==ids[j]){
             int already =0;
             for(int k=0;k<dcount;k++) {
                 if(dup[k]==ids[i]) {
                     already=1;
                      break;
                 }
             }
         }
     }
     
     
}