#include <bits/stdc++.h>
#include "gap.h"
#define F first
#define S second
#define all(x) x.begin(), x.end()
#define pb push_back
#define FIO ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)
using namespace std;
typedef long long ll;
typedef pair <ll, ll> pii;
/*
static void my_assert(int k){ if (!k) exit(1); }
static int subtask_num, N;
static long long A[100001];
static long long call_count;
long long findGap(int, int);
void MinMax(long long s, long long t, long long *mn, long long *mx)
{
int lo = 1, hi = N, left = N+1, right = 0;
my_assert(s <= t && mn != NULL && mx != NULL);
while (lo <= hi){
int mid = (lo+hi)>>1;
if (A[mid] >= s) hi = mid - 1, left = mid;
else lo = mid + 1;
}
lo = 1, hi = N;
while (lo <= hi){
int mid = (lo+hi)>>1;
if (A[mid] <= t) lo = mid + 1, right = mid;
else hi = mid - 1;
}
if (left > right) *mn = *mx = -1;
else{
*mn = A[left];
*mx = A[right];
}
if (subtask_num == 1) call_count++;
else if (subtask_num == 2) call_count += right-left+2;
}*/
//---------------------------
const ll inf = 1e18;
ll findGap(int t, int n) {
if (t == 1) {
ll x = 0, y = inf;
ll mn=0, mx=inf;
vector <ll> v;
for (int i = 0; i < (n+1)/2; i++) {
MinMax(x, y, &mn, &mx);
v.pb(mn);
v.pb(mx);
x = mn+1; y = mx-1;
}
sort(all(v)); v.erase(unique(all(v)), v.end());
ll res = 0;
for (int i = 1; i < n; i++) res = max(res, v[i]-v[i-1]);
return res;
}
ll lo=0, hi=0;
MinMax(0, inf, &lo, &hi);
ll d = (hi-lo)/(n-1);
vector <ll> v;
v = {lo, hi};
for (ll i = lo+1; i <= hi; i += d) {
ll a=0, b=0;
MinMax(i, i+d-1, &a, &b);
if (a != -1) {v.pb(a); v.pb(b);}
}
sort(all(v)); v.erase(unique(all(v)), v.end());
ll res = 0;
for (int i = 1; i < v.size(); i++) res = max(res, v[i]-v[i-1]);
return res;
}
//---------------------------
/*
int main()
{
FILE *in = stdin, *out = stdout;
my_assert(2 == fscanf(in, "%d%d", &subtask_num, &N));
my_assert(1 <= subtask_num && subtask_num <= 2);
my_assert(2 <= N && N <= 100000);
for (int i=1;i<=N;i++) my_assert(1 == fscanf(in, "%lld", A+i));
for (int i=1;i<N;i++) my_assert(A[i] < A[i+1]);
fprintf(out, "%lld\n", findGap(subtask_num, N));
fprintf(out, "%lld\n", call_count);
}*/
