#include <cstdio>
#include <cstdlib>
#include <vector>
#include <algorithm>
#include <cmath>
#include <cstring>
#include <iostream>
#include <iomanip>
#include <limits.h>
#include <set>
#include <string>
#include <queue>
#include <stack>
#include <unordered_map>
#include <unordered_set>
#include <deque>
#include <map>
#include <chrono>
#include <random>
#include <bitset>
#include <tuple>
#include <cassert>
#include "souvenirs.h"
#include <utility>
#define SZ(x) (LL)(x.size())
#define FR(i,a,b) for(LL i=(a);i<(b);++i)
#define FOR(i,n) FR(i,0,n)
#define FAST ios::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define A first
#define B second
#define mp(a,b) make_pair(a,b)
typedef long long LL;
typedef long double LD;
typedef unsigned long long ULL;
typedef unsigned __int128 U128;
typedef __int128 I128;
typedef std::pair<int,int> PII;
typedef std::pair<LL,LL> PLL;
typedef std::pair<LD,LD> PLD;
using namespace std;
const int MAXN=101;
int cnt[MAXN];
LL p[MAXN];
int n;
//n=3 -> u buy p0-1
//if u only get 1, then can calculate price of 1. take p1-1 twice
//else, u get p1+p2. p2 <= half this number
void upd(vector<int> v){
FOR(i,n) cnt[i]+=v[i];
}
void buy_souvenirs(int N, LL p0){
n=N;
pair<vector<int>, LL> res=transaction(p0-1);
if (n==2) return;
upd(res.A);
if (cnt[2]==1){
LL sum=p0-1-res.B;
transaction((sum-1)/2);
}
else{
p[1]=p0-1-res.B;
transaction(p[1]-1);
transaction(p[1]-1);
}
}
