#include <bits/stdc++.h>
using namespace std;
const long long mod = (long long)1e9 + 7;
const long long inf = (long long)1e16;
const long double eps = 1e-12;
const long long N = (int)1e5 + 5;
const long long LOGN = 19;
const long double PI = 3.14159265358979323846;
inline long long mul(long long a, long long b, long long m = mod) {
  return (long long)(a * b) % m;
}
inline long long add(long long a, long long b, long long m = mod) {
  a += b;
  if (a >= m) a -= m;
  if (a < 0) a += m;
  return a;
}
inline long long power(long long a, long long b, long long m = mod) {
  if (b == 0) return 1;
  if (b == 1) return (a % m);
  long long x = power(a, b / 2, m);
  x = mul(x, x, m);
  if (b % 2) x = mul(x, a, m);
  return x;
}
int n, m;
int mapper[N];
int pos[N][11];
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  if (0) {
    freopen("C:\\Users\\Dishant\\Desktop\\Collection-DEV c++\\input.txt", "r",
            stdin);
    freopen("C:\\Users\\Dishant\\Desktop\\Collection-DEV c++\\output.txt", "w",
            stdout);
  }
  cin >> n >> m;
  int a[n][m];
  int curr = 0;
  for (int i = 0; i < n; i++) {
    int u;
    cin >> u;
    mapper[u] = curr++;
    a[i][0] = mapper[u];
    pos[a[i][0]][0] = i;
  }
  for (int j = 1; j <= m - 1; j++) {
    for (int i = 0; i < n; i++) {
      int u;
      cin >> u;
      a[i][j] = mapper[u];
      pos[a[i][j]][j] = i;
    }
  }
  long long ans = 0;
  vector<long long> lens;
  int num = 0;
  while (num < curr) {
    int len = 1;
    int i = num + 1;
    bool ok = true;
    for (; i < curr; i++) {
      bool kk = true;
      for (int j = 0; j < m; j++) {
        if (pos[i][j] != pos[i - 1][j] + 1) {
          kk = false;
          break;
        }
      }
      if (!kk) {
        break;
      }
      len++;
    }
    num = i;
    lens.push_back(len);
  }
  for (long long i : lens) {
    ans += (i * (i + 1)) / 2ll;
  }
  cout << ans;
  return 0;
}
