#include <bits/stdc++.h>
using namespace std;
using lint = long long int;
using pint = pair<int, int>;
using plint = pair<lint, lint>;
struct fast_ios { fast_ios(){ cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(20); }; } fast_ios_;
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((lint)(x).size())
#define POW2(n) (1LL << (n))
#define FOR(i, begin, end) for(int i=(begin),i##_end_=(end);i<i##_end_;i++)
#define IFOR(i, begin, end) for(int i=(end)-1,i##_begin_=(begin);i>=i##_begin_;i--)
#define REP(i, n) FOR(i,0,n)
#define IREP(i, n) IFOR(i,0,n)
template<typename T> void ndarray(vector<T> &vec, int len) { vec.resize(len); }
template<typename T, typename... Args> void ndarray(vector<T> &vec, int len, Args... args) { vec.resize(len); for (auto &v : vec) ndarray(v, args...); }
template<typename T> bool mmax(T &m, const T q) { if (m < q) {m = q; return true;} else return false; }
template<typename T> bool mmin(T &m, const T q) { if (m > q) {m = q; return true;} else return false; }
template<typename T1, typename T2> pair<T1, T2> operator+(const pair<T1, T2> &l, const pair<T1, T2> &r) { return make_pair(l.first + r.first, l.second + r.second); }
template<typename T1, typename T2> pair<T1, T2> operator-(const pair<T1, T2> &l, const pair<T1, T2> &r) { return make_pair(l.first - r.first, l.second - r.second); }
template<typename T> istream &operator>>(istream &is, vector<T> &vec){ for (auto &v : vec) is >> v; return is; }
///// This part below is only for debug, not used /////
template<typename T> ostream &operator<<(ostream &os, const vector<T> &vec){ os << "["; for (auto v : vec) os << v << ","; os << "]"; return os; }
template<typename T> ostream &operator<<(ostream &os, const deque<T> &vec){ os << "deq["; for (auto v : vec) os << v << ","; os << "]"; return os; }
template<typename T> ostream &operator<<(ostream &os, const set<T> &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }
template<typename T> ostream &operator<<(ostream &os, const unordered_set<T> &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }
template<typename T> ostream &operator<<(ostream &os, const multiset<T> &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }
template<typename T> ostream &operator<<(ostream &os, const unordered_multiset<T> &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }
template<typename T1, typename T2> ostream &operator<<(ostream &os, const pair<T1, T2> &pa){ os << "(" << pa.first << "," << pa.second << ")"; return os; }
template<typename TK, typename TV> ostream &operator<<(ostream &os, const map<TK, TV> &mp){ os << "{"; for (auto v : mp) os << v.first << "=>" << v.second << ","; os << "}"; return os; }
template<typename TK, typename TV> ostream &operator<<(ostream &os, const unordered_map<TK, TV> &mp){ os << "{"; for (auto v : mp) os << v.first << "=>" << v.second << ","; os << "}"; return os; }
#define dbg(x) cerr << #x << " = " << (x) << " (L" << __LINE__ << ") " << __FILE__ << endl;
///// END /////

vector<vector<int>> cou;
vector<vector<int>> n, rect;

lint D;
bool solve(lint C)
{
    vector<vector<int>> imos(D * 2 + 1, vector<int>(D * 2 + 1));
    REP(i, D) REP(j, D)
    {
        lint nb = cou[i][j];
        if ((C / D + 1) * (C / D + 1) < nb) return false;

        if (((C + 1) / D) * ((C + 1) / D) >= nb)
        {
            imos[0][0]++;
            continue;
        }

        int m = C % D;

        if (rect[i][j])
        {
            imos[max(i - m, 0)][0]++;
            imos[i + 1][0]--;
            imos[i + D - m][0]++;
            imos[i + D + 1][0]--;
            imos[0][max(j - m, 0)]++;
            imos[0][j + 1]--;
            imos[0][j + D - m]++;
            imos[0][j + D + 1]--;
        }

        int add = rect[i][j] ? -1 : 1;
        for (int ofx = 0; ofx <= D; ofx += D)
        {
            for (int ofy = 0; ofy <= D; ofy += D)
            {
                int x = max(i - m + ofx, 0);
                int y = max(j - m + ofy, 0);
                imos[x][y] += add;
                imos[x][j + ofy + 1] -= add;
                imos[i + ofx + 1][y] -= add;
                imos[i + ofx + 1][j + ofy + 1] += add;
            }
        }
    }
    REP(i, 2 * D) REP(j, 2 * D) imos[i][j + 1] += imos[i][j];
    REP(i, 2 * D) REP(j, 2 * D) imos[i + 1][j] += imos[i][j];
    REP(i, 2 * D) REP(j, 2 * D) if (imos[i][j] >= D * D) return true;
    return false;
}

int main()
{
    int N;
    cin >> N >> D;
    cou.resize(D, vector<int>(D));
    while (N--)
    {
        int x, y;
        cin >> x >> y;
        cou[x % D][y % D]++;
    }
    n.resize(D, vector<int>(D));
    rect.resize(D, vector<int>(D));
    REP(i, D) REP(j, D)
    {
        while(n[i][j] * n[i][j] < cou[i][j]) n[i][j]++;
        if (n[i][j] * n[i][j] - cou[i][j] >= n[i][j]) rect[i][j] = 1;
    }

    lint l = 0, r = 1e8;
    while (r > l + 1)
    {
        lint c = (l + r) / 2;
        (solve(c) ? r : l) = c;
    }
    cout << r << endl;
}


Measured memory_bytes: 27880