#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <memory.h>
#include <math.h>
#include <assert.h>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <string>
#include <algorithm>
#include <iostream>
#include <functional>
#include <unordered_set>
#include <bitset>
#include <time.h>
#include <limits.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define Fi first
#define Se second
#define pb(x) push_back(x)
#define szz(x) (int)x.size()
#define rep(i,n) for(int i=0;i<n;i++)
#define all(x) x.begin(),x.end()
typedef tuple<int, int, int> t3;
int n, m, X[10][10];
int ar[10];
int ans = 100500;
void dfs(int x) {
if(x == m) {
int Y[6][6];
int cnt = 0;
rep(i, m) cnt += min(ar[i], n - ar[i]);
rep(i, n) rep(j, m) Y[i][j] = X[(i+ar[j])%n][j];
int ok = 1;
rep(i, n) rep(j, m) if(Y[i][j] != Y[i][0]) ok = 0;
if(ok) ans = min(ans, cnt);
map <vector <int>, int> Mx; int cs = 0;
int Z[6][6], dp[6][6];
rep(i, n) rep(j, m) {
vector <int> w;
rep(k, m) w.pb(Y[i][(j+k)%m]);
if(Mx.find(w) == Mx.end()) Mx[w] = ++cs;
Z[i][j] = Mx[w];
}
rep(j, m) dp[0][j] = min(j, m-j);
for(int i=1;i<n;i++) {
rep(j, m) dp[i][j] = 1e9;
rep(j, m) rep(k, m) if(Z[i][j] == Z[i-1][k]) {
dp[i][j] = min(dp[i][j], dp[i-1][k] + min(j, m-j));
}
}
cnt += *min_element(dp[n-1], dp[n-1] + m);
ans = min(ans, cnt);
return;
}
rep(i, n) {
ar[x] = i;
dfs(x + 1);
}
}
int main() {
scanf("%d%d", &n, &m);
rep(i, n) rep(j, m) scanf("%d", X[i] + j);
dfs(0);
printf("%d\n", ans);
return 0;
}
