#include <bits/stdc++.h>

int n, m;

std::string tagid(std::string str) {
    std::string s = str + str, k, min;
    min = str;

    for(int i = 1; i < m; i++) {
        k = std::string(&s[i], &s[i+m]);
        if(min > k) min = k;
    }
    return min;
}

int main() {
    long long count = 0;
    std::ios::sync_with_stdio(false);
    std::cin.tie(0);
    std::string cache;
    std::vector<std::string> ids;

    std::cin >> n >> m;
    for(int i = 0; i < n; i++) {
        std::cin >> cache; 
        ids.push_back(tagid(cache));
    }

    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n-i-1; j++) {
            if(ids[i] == ids[n-j-1]) count++;
        }
    }
    std::cout << count;
}