#include "prize.h"
const int MAXN = 2e5 + 1;
std::vector<int> ans[MAXN];
bool off[MAXN];
int countOff[MAXN];
void add(int i)
{
while (i <= MAXN)
{
countOff[i]++;
i += i & (-i);
}
}
int sum(int i)
{
int res = 0;
while (i > 0)
{
res += countOff[i];
i -= i & (-i);
}
return res;
}
int searchgood(std::vector<int> space, int non)
{
if (space.empty())
return -1;
int middle = space[space.size() / 2];
std::vector<int> a = ask(middle);
if (a[0] + a[1] == 0)
return middle;
if (a[0] + a[1] != non)
{
off[middle] = true;
add(middle + 1);
return -1;
}
if (a[0] - sum(middle) != 0)
return searchgood(std::vector<int>(space.begin(), space.begin() + space.size() / 2), non);
return searchgood(std::vector<int>(space.begin() + space.size() / 2 + 1, space.end()), non);
}
int find_best(int n)
{
if (n < 474)
{
for (int i = 0; i < n; i++)
if (ask(i)[0] + ask(i)[1] == 0)
return i;
return -1;
}
int step = n / 474;
int nonLollipop = 0;
for (int iBlock = 0; iBlock < n; iBlock += step)
{
ans[iBlock] = ask(std::min(iBlock + step, n) - 1);
nonLollipop = std::max(nonLollipop, ans[iBlock][0] + ans[iBlock][1]);
}
int done = 0;
for (int iBlock = 0; iBlock < n; iBlock += step)
{
int end = std::min(iBlock + step, n);
int idk = 0;
while (end != iBlock && ans[iBlock][0] + ans[iBlock][1] != nonLollipop)
{
if (ans[iBlock][0] + ans[iBlock][1] == 0)
return end - 1;
off[end - 1] = true;
add(end);
idk++;
end--;
ans[iBlock] = ask(end - 1);
}
if (end == iBlock)
{
done += idk;
continue;
}
while (ans[iBlock][0] > done)
{
std::vector<int> sspace;
for (int iBox = iBlock; iBox < end; iBox++)
if (!off[iBox])
sspace.emplace_back(iBox);
int pos = searchgood(sspace, nonLollipop);
if (pos != -1)
return pos;
done++;
}
done += idk;
}
return -1;
}
