#include "gap.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(i, n) for(int i = 1; (i) <= (n); ++i)
#define forn(i, l, r) for(int i = (l); i <= (r); ++i)
#define ford(i, r, l) for(int i = (r); i >= (l); --i)
#define FOR(i, n) for(int i = 0; i < (n); ++i)
#define FORD(i, n) for(int i = ((n) - 1); i >= 0; --i)
template<typename T> bool maximize(T &res, const T &val) { if (res < val){ res = val; return true; }; return false; }
int findGap(int T, int N)
{
vector<ll> a(N + 2);
if(T == 1)
{
int l = 1, r = N;
ll lb = 0, rb = 1e18;
while(l <= r)
{
ll x, y;
MinMax(lb, rb, &x, &y);
a[l] = x; ++l;
a[r] = y; --r;
lb = x + 1;
rb = y - 1;
}
ll res = 0;
rep(i, N - 1) maximize(res, a[i + 1] - a[i]);
return res;
}
ll x, y;
MinMax(0, 1e18, &x, &y);
a[1] = x, a[N] = y;
ll res = 0;
ll Min_step = (a[N] - a[1] - 1) / (N - 1) + 1;
if(N == 2) return a[N] - a[1];
for(ll i = a[1], pre = a[1]; i <= a[N]; i += Min_step + 1)
{
MinMax(i, i + Min_step, &x, &y);
if(x != -1) maximize(res, x - pre), pre = y;
}
return res;
}
