// #pragma optimize("Ofast")
#include "bits/stdc++.h"
#define int long long
#define all(v) (v).begin(), (v).end()
#define pb push_back
#define em emplace_back
#define mp make_pair
#define F first
#define S second
using namespace std;
template<class C>
using vec = vector<C>;
using vi = vector<int>;
using vpi = vector<pair<int, int> >;
using pii = pair<int, int>;
void MinMax(long long s, long long t, long long *mn, long long *mx);
const int INF = 1e18;
class solver {
public:
pii query(int a, int b) {
int u, v;
MinMax(a, b, &u, &v);
return {u, v};
}
int answer;
solver(int t, int n) {
vi a(n);
int l = 0, r = n - 1;
int L = 0, R = INF;
while (l <= r) {
auto [f, s] = query(L, R);
a[l] = f;
a[r] = s;
L = f + 1;
R = s - 1;
l++;
r--;
}
int res = 0;
for (int i = 1; i < n; i++) {
res = max(res, a[i] - a[i - 1]);
}
answer = res;
}
};
int findGap(int32_t t, int32_t n) {
solver sol(t, n);
return sol.answer;
}
#undef int
