#define _CRT_SECURE_NO_WARNINGS
#include<sstream>
#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<climits>
#include<cmath>
#include<string>
#include<vector>
#include<set>
#include<map>
#include<queue>
#include<numeric>
#include<functional>
#include<algorithm>
#include<bitset>
#include<tuple>
#include<unordered_set>
#include<random>
using namespace std;
#define INF (1<<29)
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define all(v) v.begin(),v.end()
#define uniq(v) v.erase(unique(all(v)),v.end())



vector<int> idx[100 * 200 * 200 + 1];

vector<int> val[200 * (2 * 100 + 2)];
int cnt[200 * (2 * 100 + 2)];



int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	
	int n, m;
	cin >> n >> m;
	int ans = 2 * n - 1;
	rep(i, m) {
		int b = i*(2 * n + 2);
		rep(y,n)rep(x,n) {
			int c;
			cin >> c;
			idx[c].push_back(b + y);
			val[b + y].push_back(c);
			idx[c].push_back(b + n + x);
			val[b + n + x].push_back(c);

			if (y==x) {
				idx[c].push_back(b + 2 * n);
				val[b + 2 * n].push_back(c);
			}
			if (n - 1 - y == x) {
				idx[c].push_back(b + 2 * n + 1);
				val[b + 2 * n + 1].push_back(c);
			}
		}
	}
	rep(i, m) {
		rep(j, 2 * n + 2) {
			for (int v : val[i*(2 * n + 2) + j]) {
				for (int k : idx[v]) {
					if (!(i*(2 * n + 2) <= k && k < (i + 1)*(2 * n + 2))) {
						ans = min(ans, 2 * n - ++cnt[k] - 1);
					}
				}
			}
			for (int v : val[i*(2 * n + 2) + j]) {
				for (int k : idx[v]) {
					if (!(i*(2 * n + 2) <= k && k < (i + 1)*(2 * n + 2))) {
						--cnt[k];
					}
				}
			}
		}
	}

	cout << ans << endl;



	return 0;
}