#include "prize.h"
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair < int , int >
#define fi first
#define se second
#define FOR(i, a, b) for (int i = (a), _b = (b); i <= _b; i ++)
#define FORD(i, a, b) for (int i = (a), _b = (b); i >= _b; i --)
#define REP(i, n) for (int i = 0, _n = (n); i < _n; i ++)
#define bit(x, i) (((x) >> (i)) & 1ll)
#define mask(x) (1ll << (x))
#define mem(f, x) memset(f, x, sizeof(f))
#define sz(x) (int32_t) (x.size())
int find_best(int n) {
auto tmp = ask(0);
if (!tmp[1]) {
return 0;
}
int pos = 0, cntl = tmp[0], cntr = tmp[1];
while (true) {
int l = pos + 1, r = n - 1, svl, svr;
while (l <= r) {
int mid = (l + r) >> 1;
auto tmp = ask(mid);
if (tmp[0] != cntl || tmp[1] != cntr) {
pos = mid;
svl = tmp[0];
svr = tmp[1];
r = mid - 1;
}
else {
l = mid + 1;
}
}
if (!svl && !svr) {
return pos;
}
cntl = svl;
cntr = svr;
}
}
