#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define l(a, b, i) for (ll i = a; i < b; i++)
#define rl(a, b, i) for (ll i = a; i >= b; i--)
#define vpair vector<pair<ll, ll>>
#define inf LLONG_MAX
#define ninf LLONG_MIN
int main() {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
ll N, T; cin >> N >> T; vector<ll> vec(N);
l(0, N, i) cin >> vec[i];
sort(vec.begin(), vec.end());
if (T == 1) {
cout << 0; return 0;
}
if (T == 2) {
ll odd = 0, even = 0;
l(0, N, i) {
if (vec[i] % 2 == 1) odd++;
else even++;
}
if (odd > 0 && even > 0) {
cout << 1; return 0;
}
else {
cout << 0; return 0;
}
}
if (N == 2) {
ll dif = vec[1] - vec[0];
ll time = dif / T;
ll time2 = time;
if (dif % T > 0) time2++;
cout << min(abs(vec[0] - (vec[1] - time * T)), abs((vec[0] - T) - (vec[1] - time2 * T)));
return 0;
}
}
