#include <iostream>
#include <vector>

using namespace std;

int main()
{
    int n, m, i, j, k, x;
    cin >> n >> m;

    vector<string> patterns(1);
    patterns.reserve(n);

    cin >> patterns[0];

    vector<int> count(1, 1);
    count.reserve(n);

    string tag;

    for (i = 1; i < n; i++)
    {
        cin >> tag;
        x = 0, k = 0;

        for (j = 0; j < patterns.size(); j++)
        {
            for (k = 0; k < m; k++)
            {
                while (x < m && (x + k < m && tag[x+k] == patterns[j][x]) || (x + k >= m && tag[x + k - m] == patterns[j][x]))
                {
                    x++;
                }
            
                if (x == m)
                {
                    count[j]++;
                    break;
                }

                x = 0;
            }
            if (x == m)
            {
                break;
            }
        }

        if (x != m)
        {
            patterns.push_back(tag);
            count.push_back(1);
        }
    }

    int sum = 0;

    for (i = 0; i < count.size(); i++)
    {
        if (count[i] > 1)
        {
            sum += (count[i] * (count[i]-1)) >> 1;
        }
    }

    cout << sum;
}
//4 4
//abcd
//xbcd
//cdab
//dabc