#include "prize.h"
#include <bits/stdc++.h>
using namespace std;
using vi = vector <int>;
using pii = pair <int, int>;
#define pb push_back
#define mp make_pair
#define F first
#define S second
#define N 200005
map < int, vector<int> > query;
int mx;
int fen[N];
bool u[N];
void add(int x){
x++;
if (!u[x]) u[x] = 1;
else return;
while (x < N){
fen[x]++;
x += (x & (-x));
}
}
int sum(int x){
x++;
int s = 0;
while (x){
s = s + fen[x];
x -= (x & (-x));
}
return s;
}
vector < int > askk(int x){
if( query.find( x ) == query.end() ){
return query[x] = ask(x);
}
return query[x];
}
int gg(int l, int r){
vi tmp;
if (l > r) return -1;
// cerr << l<<" " << r<< '\n';
if (l == r) {
tmp = askk(l);
add(l);
if (tmp[0] + tmp[1] == 0) return l;
return -1;
}
while(l <= r){
tmp = askk(r);
if ((tmp[0] + tmp[1]) == 0) {
add(r);
return r;
}
if (tmp[0] + tmp[1] == mx) break;
add(r);
r--;
}
// cerr <<tmp[1]<<" "<< tmp[0] <<" "<< sum(l - 1)<< " "<< l << " "<< r<< endl;
if (l > r) return -1;
if (tmp[0] == sum(l - 1)) return -1;
if (l == r) return gg(l, r);
int mid = (l + r) / 2;
int ind = gg(l , mid);
if (ind != -1) return ind;
if (tmp[0] != sum(mid)) return gg(mid + 1, r - 1);
return - 1;
}
int find_best(int n) {
int s[505];
for (int j = 0;j < 10;j++){
int i = rand() % n;
vi ans = askk(i);
s[i] = ans[0] + ans[1];
if (!s[i]) return i;
mx = max(mx, s[i]);
}
// cerr << sum(499)<< " "<< mx<< endl;
return gg(0, n - 1);
}
