#include <iostream>
using namespace std;
struct node {
int roll;
node *next;
};
node *root = NULL;
void append(int roll)
{
if(root==NULL) {
root = new node();
root->roll = roll;
root->next = NULL;
}
else {
node *curn = root;
while(curn->next!=NULL)
curn=root->next;
}
}
int main()
{
return 0;
}
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