#include <bits/stdc++.h>

using namespace std;

#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;

bool find(int j, vector<vi>& g, vi& btoa, vi& vis) {
    if (btoa[j] == -1) return 1;

    vis[j] = 1; int di = btoa[j];

    for (int e : g[di]) {
        if (!vis[e] && find(e, g, btoa, vis)) {
            btoa[e] = di;

            return 1;
        }
    }

    return 0;
}

int dfsMatching(vector<vi>& g, vi& btoa) {
    vi vis;

    rep(i,0,sz(g)) {
        vis.assign(sz(btoa), 0);

        for (int j : g[i]) {
            if (find(j, g, btoa, vis)) {
                btoa[j] = i;

                break;
            }
        }
    }

    return sz(btoa) - (int)count(all(btoa), -1);
}

void c_graph(vector<vector<int>> &adj, vector<int> &color, int n, int col){
    if(color[n] != -1){
        assert(color[n] == col);
    }else{
        color[n] = col;

        for(const int &v : adj[n])
            c_graph(adj, color, v, 1 - col);
    }
}

int main(){
    cin.tie(NULL)->sync_with_stdio(false);

    int n;
    cin >> n;

    vector<string> s(n);
    for(int i = 0; i < n; i++)
        cin >> s[i];
    
    vector<vector<int>> adj(n, vector<int>());
    for(int i = 0; i < n; i++){
        for(int j = 0; j < n; j++){
            if(i != j){
                int diffs = 0;

                for(int k = 0; k < s[i].size(); k++)
                    if(s[i][k] != s[j][k])
                        diffs++;

                if(diffs == 2)
                    adj[i].push_back(j);
            }
        }
    }

    vector<int> color(n, -1);
    for(int i = 0; i < n; i++)
        if(color[i] == -1)
            c_graph(adj, color, i, 0);
    
    int r_part = 0;
    unordered_map<int, int> b_mapping;

    for(int i = 0; i < n; i++)
        if(color[i])
            b_mapping[i] = r_part++;

    int ind = 0;
    vector<vector<int>> b_adj(n - r_part, vector<int>());
    for(int i = 0; i < n; i++){
        if(!color[i]){
            for(const int &v : adj[i])
                b_adj[ind].push_back(b_mapping[v]);

            ind++;
        }
    }

    if(r_part == 0){
        cout << n << "\n";
    }else{
        vector<int> btoa(r_part, -1);
        cout << n - dfsMatching(b_adj, btoa) << "\n";
    }
}