#include "cave.h"
#include <bits/stdc++.h>
#define FIXED_FLOAT(x) std::fixed <<std::setprecision(20) << (x)
#define all(v) (v).begin(), (v).end()
using namespace std;
#define forn(i,n) for (int i = 0; i < (n); ++i)
#define rforn(i, n) for(int i = (n) - 1;i >= 0;--i)
using ll = long long;
int mod = (ll)1e9 + 7;
#define PI acos(-1)
typedef pair<int, int> pairs;
const int INF = 1e9 + 1;
const int N = 2e5 + 100;
const double eps = 1e-7;
template <class T> using V = vector<T>;
template <class T> using VV = V<V<T>>;
template <typename XPAX>
void ckma(XPAX &x, XPAX y) {
x = (x < y ? y : x);
}
template <typename XPAX>
void ckmi(XPAX &x, XPAX y) {
x = (x > y ? y : x);
}
void exploreCave(int n) {
/* ... */
bool fin[n];
int cur[n], st[n];
int door[n];
forn(i, n) {
fin[i] = false;
door[i] = -1;
cur[i] = 0;
}
auto redo = [&]() {
forn(i, n) if(!fin[i]) st[i] ^= 1;
};
forn(i, n) {
forn(j, n) st[j] = cur[j];
int mx = tryCombination(st);
if(mx != i)
redo();
int l = 0, r = n - 1;
while(l < r) {
int mid = (l + r) >> 1;
for(int j = l;j <= mid;++j) {
if(!fin[j]) st[j] ^= 1;
}
int x = tryCombination(st);
if(x != i) {
r = mid;
for(int j = l;j <= mid;++j) {
if(!fin[j])st[j] ^= 1;
}
}
else {
l = mid + 1;
}
}
fin[l] = 1;
cur[l] = st[l] ^ 1;
door[l] = i;
}
return answer(cur, door);
}
