#include <bits/stdc++.h>
#include <iostream>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
typedef tree<ll,null_type,less_equal<ll>,rb_tree_tag,tree_order_statistics_node_update> order_set;
mt19937 mt_rand(chrono::high_resolution_clock::now().time_since_epoch().count());
//uniform_int_distribution<int> gen; ///(min, max)
//int random() {return gen(mt_rand);}
const int mxN=1e5+5;
const int mod=998244353;
const int mxlogN=40;
const int mxK=26;
const ll inf=1e18;
const int K=600;
void MinMax(ll s, ll t, ll *mn, ll *mx);
ll a[mxN];
ll findGap(int t, int n)
{
if(t==1)
{
ll mn=0,mx=inf;
for(int l=0, r=n-1; l<=r; l++, r--)
{
MinMax(mn,mx,&a[l],&a[r]);
mn=a[l]+1;
mx=a[r]-1;
}
ll ans=0;
for(int i=1; i<n; i++) ans=max(ans,a[i]-a[i-1]);
return ans;
}
ll mn,mx;
MinMax(0,inf,&mn,&mx);
ll gap=(mx-mn+n-1-1)/(n-1);
ll x=mn,y=mn;
while(x<mx)
{
ll mn2, mx2;
MinMax(x+1,min(inf,y+gap),&mn2,&mx2);
y+=gap;
if(~mn2)
{
gap=max(gap,mn2-x);
x=mx2;
}
}
return gap;
}
/*
int main()
{
}*/
/*
7 3
4 1 3 4 0 2 3
*/
