#include "gap.h"
#include<bits/stdc++.h>
#define lf double
#define ll long long
#define cc pair<char,char>
#define ull unsigned ll
#define ii pair<int,int>
#define li pair<ll,int>
#define iii pair<int,ii>
#define iiii pair<ii,ii>
#define iiii2 pair<int,iii>
#define lii pair<ll,ii>
#define lolo pair<ll,ll>
#define heap priority_queue
#define mp make_pair
#define st first
#define nd second
#define pb push_back
#define pf push_front
#define ppb pop_back
#define ppf pop_front
#define all(x) x.begin(),x.end()
#define len(x) strlen(x)
#define sz(x) (int) x.size()
#define orta ((bas+son)/2)
#define min3(x,y,z) min(min(x,y),z)
#define max3(x,y,z) max(max(x,y),z)
#define umin(x,y) x=min(x,y)
#define umax(x,y) x=max(x,y)
#define dbgs(x) cerr<<(#x)<<" --> "<<(x)<<" "
#define dbg(x) cerr<<(#x)<<" --> "<<(x)<<endl;getchar()
#define MOD 998244353
#define inf 1000000000000000000ll
#define M 10000002
#define LOG 40
#define magic 100
#define KOK 250
#define EPS 0.0025
#define pw(x) ((1ll)<<(x))
#define PI 3.1415926535
using namespace std;
long long findGap(int T, int N) {
ll ans=0;
ll bas,son;
MinMax(0,inf,&bas,&son);
ll ratio=(son-bas-1)/(N-1);
vector<ll> possible;
possible.pb(bas);
for(int i=1;i<N;i++) {
ll v1,v2;
MinMax(bas+ratio*(i-1)+1,max(bas+ratio*i,bas+ratio*(i-1)+1),&v1,&v2);
if(v1!=-1) {
if(v1!=v2 || (sz(possible) && possible.back()!=v1)) possible.pb(v1);
possible.pb(v2);
}
}
if(possible.back()!=son) possible.pb(son);
for(int i=0;i<sz(possible)-1;i++) {
umax(ans,possible[i+1]-possible[i]);
}
return ans;
}
