#include "iostream"
#include "climits"
#include "list"
#include "queue"
#include "stack"
#include "set"
#include "functional"
#include "algorithm"
#include "string"
#include "map"
#include "unordered_map"
#include "unordered_set"
#include "iomanip"
#include "cmath"
#include "random"
#include "bitset"
#include "cstdio"
#include "numeric"
#include "cassert"
#include "ctime"

using namespace std;

constexpr long long int MOD = 1000000007;
//constexpr int MOD = 1000000007;
//constexpr int MOD = 998244353;
//constexpr long long int MOD = 998244353;
constexpr double EPS = 1e-8;

int N, M, K, H, W, L, R;
//long long int N, M, K, H, W, L, R;

class Segment_Tree {
	vector<int>v;
	int num;
	int ret;
	int Update(int place) {
		if (place >= v.size() / 2) {
			return v[place];
		}
		v[place] = max(Update(place * 2), Update(place * 2 + 1));
		return v[place];
	}
public:
	Segment_Tree(int n) {
		n++;
		num = 1;
		while (num < n * 2) {
			num *= 2;
		}
		v.resize(num, -MOD);
	}
	void Insert(int place, long long int num, bool update) {
		place += v.size() / 2;
		v[place] = num;
		if (!update)return;
		place /= 2;
		while (place) {
			v[place] = max(v[place * 2], v[place * 2 + 1]);
			place /= 2;
		}
	}
	void TopDown() {
		Update(1);
	}
	int RMQ(int a, int b) {
		ret = INT_MIN;
		b++;
		for (a += num / 2, b += num / 2; a < b; a >>= 1, b >>= 1) {
			if (a & 1)ret = max(ret, v[a++]);
			if (b & 1)ret = max(ret, v[--b]);
		}
		return ret;
	}
};

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);

	cin >> N >> K;
	vector<vector<int>>v(K, vector<int>(K));
	for (int i = 0; i < N; i++) {
		cin >> W >> H;
		v[H%K][W%K]++;
	}
	vector<vector<int>>hbox(K);
	for (int i = 0; i < K; i++) {
		for (int j = 0; j < K; j++) {
			if (v[i][j])hbox[i].push_back(j);
		}
	}
	int mx = 0;
	for (auto i : v)for (auto j : i)mx = max(mx, j);
	L = (sqrt(mx) - 1)*K - 1;
	R = sqrt(mx)*K + K - 1;
	Segment_Tree r(K);
	vector<int>num(K);
	vector<int>rr(K);
	while (R - L > 1) {
		int mid = (R + L) / 2;
		bool flag = false;
		for (int i = 0; i < K; i++) {
			num[i] = (mid - i + K) / K;
		}
		for (int l = 0; l < K; l++) {
			int mi = MOD;
			for (int i = 0; i < K; i++) {
				rr[i] = 0;
				for (auto j : hbox[i]) {
					if (!num[i]) {
						rr[i] = MOD;
						break;
					}
					rr[i] = max(rr[i], (v[i][j] - 1) / num[i] * K + j + ((j < l) ? K : 0));
				}
			}
			for (int i = 0; i < K; i++) {
				r.Insert(i, rr[i], false);
			}
			r.TopDown();
			mi = min(mi, r.RMQ(0, K - 1));
			if (mi - l <= mid) {
				flag = true;
				break;
			}
			if (0 == (mid + 1) % K)continue;
			for (int d = 0; d < K; d++) {
				num[d]--;
				int nx = (d + 1 + mid) % K;
				num[nx]++;
				if (d == K - 1)continue;
				int nr = 0;
				for (auto j : hbox[d]) {
					if (!num[d]) {
						nr = MOD;
						break;
					}
					nr = max(nr, (v[d][j] - 1) / num[d] * K + j + ((j < l) ? K : 0));
				}
				r.Insert(d, nr, true);
				nr = 0;
				for (auto j : hbox[nx]) {
					if (!num[nx]) {
						nr = MOD;
						break;
					}
					nr = max(nr, (v[nx][j] - 1) / num[nx] * K + j + ((j < l) ? K : 0));
				}
				r.Insert(nx, nr, true);
				mi = min(mi, r.RMQ(0, K - 1));
				if (mi - l <= mid) {
					flag = true;
					break;
				}
			}
			if (flag)break;
			if (mi - l - 1 > mid) {
				l += mi - l - 1 - mid;
			}
		}
		if (flag) {
			R = mid;
		}
		else {
			L = mid;
		}
	}
	cout << R << endl;
}

Measured memory_bytes: 4736