#include "gap.h"
#include <set>
#define NUM_MAX 1000000000000000000
#define R_MAX 1152921504606846976
#define max2(x,y) (x>y?x:y)
#define min2(x,y) (x<y?x:y)
using namespace std;
int n;
set<long long> S;
set<pair<long long,long long> > pass;
long long f1() {
long long l = 0, r = NUM_MAX;
long long t1, t2, res = 0;
while (l <= r) {
MinMax(l, r, &t1, &t2);
if (t1 < 0) break;
S.insert(l = t1), S.insert(r = t2);
l++, r--;
if (S.size() == n) break;
}
t1 = NUM_MAX;
for (auto i : S) res = max2(res, i - t1), t1 = i;
return res;
}
long long get_pass(long long x) {
set<pair<long long, long long>>::iterator it = pass.upper_bound({ x,-1 });
if (it == pass.end()) return -1;
if (it->first == x) return it->second;
return -1;
}
bool Can(long long len) {
long long back_MAX = NUM_MAX;
long long t1, t2;
for (long long s = 0; s <= NUM_MAX; s += len) {
t2 = get_pass(s);
if (t2 > 0) { s = t2 - len; continue; }
MinMax(s, min2(NUM_MAX, s + len - 1), &t1, &t2);
if (t1 < 0) { pass.insert({ s,s + len }); continue; }
if (t1 - back_MAX >= len) return true;
back_MAX = t2;
} return false;
}
long long f2() {
long long l = 1, r = R_MAX, mid;
while (l <= r) {
mid = (l + r) / 2;
if (Can(mid)) l = mid + 1;
else r = mid - 1;
} return l - 1;
}
long long findGap(int T, int _n) {
n = _n;
if (T == 1) return f1();
else return f2();
}
