#include "souvenirs.h"
#include <utility>
#include <vector>
#include <iostream>
using namespace std;
void buy_souvenirs(int N, long long P0) {
pair<vector<int>, long long> res;
long long curp;
if (N==2) {
transaction(P0-1); return;
} else
if (N==3) {
res=transaction(P0-1);
curp=(P0-1-res.second);
if ((int)res.first.size()==2) {
transaction(curp/2);
return;
} else {
transaction(curp-1); transaction(curp-1);
return;
}
} else
if (P0==N) {
curp=P0-1;
for (int i=1;i<=N-1;i++){
for (int j=1;j<=i;j++) transaction(curp);
curp--;
}//i
return;
} else {
curp=P0-1;
for (int i=1;i<=N-1;i++){
for (int j=1;j<=i;j++) res=transaction(curp);
if (res.second==0LL) curp--;
else curp=curp-2LL;
}//i
return;
}
return;
}
