#include "souvenirs.h"
#include <utility>
#include <vector>
#include <bits/stdc++.h>
using namespace std;
void buy_souvenirs(int N, long long P0) {
  	pair<vector<int>, long long> res = transaction(P0-1);
  	int a=res.second;
  	if(a==0){
  	    if(P0%2==0)transaction(P0/2-1);
  	    else transaction(P0/2);
  	}
	else{
	    transaction(a/2);
	}
  	return;
}
/*
3
4 3 1
*/
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