#include <iostream>
using namespace std;
int main()
{
    int k, n, a[11][21] = { 0 };
    cin >> k >> n;
    for (int i = 1; i <= k; i++) {
        for (int j = 1; j <= n; j++) {
            cin >> a[i][j] ;
        }
    }
    int c[21][21] = { 0 };
    bool ce[21][21] = { 0 };
    for (int i = 1; i <= n; i++) {
        for (int j = i + 1;j<=n; j++) {
            c[a[1][i]][0]++;
            c[a[1][i]][c[i][0]] = a[1][j];
            ce[a[1][i]][c[i][0]] = 1;
        }
    }
    for (int i = 1; i <= k; i++) { //k
        for (int e = 1; e <= n; e++) {
            for (int j = 1; j <= c[a[i][e]][0]; j++) { //
                if (ce[a[i][e]][j] == 1) {
                    c[a[i][e]][0]--;
                    ce[a[i][e]][j] = 0;
                    for (int w = e + 1; w <= n; w++) {
                        if (a[i][w] == c[a[i][e]][j]) {
                            c[a[i][e]][0]++;
                            ce[a[i][e]][j] = 1;
                        }
                    }
                }
            }
        }
    }
    int ans=0;
    for(int i=1;i<=n;i++){
        ans+=c[i][0];
    }
    cout<<ans;
}