#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>

#define el '\n'
#define FIO ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);

using namespace std;
using namespace __gnu_pbds;

typedef long long ll;
typedef unsigned uint;
typedef __int128 bint;
typedef long double ld;
typedef complex<ld> pt;
typedef unsigned long long ull;

template<typename T, typename X>
using hashTable = gp_hash_table<T, X>;
template<typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<typename T>
using ordered_multiset = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>;

// mt19937_64 for unsigned long long
#define el "\n"
mt19937 rng(std::chrono::system_clock::now().time_since_epoch().count());
const int mod = 998244353, N = 1e5 + 5;
char gr[1005][13];
int n, k, ans;

int get(string key)
{
    int cur = 1e9, cnt = 0;
    for(int i = 1; i <= n; i++)
    {
        cnt = 0;
        for(int j = 0; j < k; j++)
        {
            if(gr[i][j] == key[j])
            {
                cnt++;
            }
        }
        cur = min(cur, cnt);
    }
    return cur;
}

void solve(string key)
{
    if(key.size() == k)
    {
        ans = max(ans, get(key));
        return;
    }
    solve(key + 'T');
    solve(key + 'F');
    return;
}

void doWork()
{
    cin >> n >> k;
    for(int i = 1; i <= n; i++)
    {
        for(int j = 0; j < k; j++)
        {
            cin >> gr[i][j];
        }
    }
    solve("");
    cout << ans << el;
}

signed main()
{
    FIO
    int T = 1;
//    cin >> T;
    for(int i = 1; i <= T; i++)
        doWork();
}