#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;

#define pb push_back

const ld pi = 3.14159265358979323846;
const ll INF = 1e18;
const int mod = (int)1e9 + 7;

template<typename T>
T chmax(T a, T b) {
    return a > b ? a : b;
}

template<typename T>
T chmin(T a, T b) {
    return a > b ? b : a;
}

const int N = 3e3 + 1, M = N * 2;


void solve() {
    int n;
    cin >> n;

    map<string, int> mp;
    for(int i = 0; i < n; i++){
        string s;
        cin >> s;
        mp[s]++;
    }

    vector<int> a;
    for(auto [k, v] : mp){
        a.pb(v);
    }

    sort(a.begin(), a.end());

    int qwq = 0;

    for(int i = 0, j = a.size() - 1; i < j; ){
        if(a[j] > a[i]){
            qwq += a[i] * 2;
            a[j] -= a[i];
            i++;
        }
        else if(a[i] > a[j]){
            qwq += a[j] * 2;
            a[i] -= a[j];
            j--;
        }
        else{
            qwq += a[i] * 2;
            i++, j--;
        }
    }
    cout << (qwq == n ? qwq : qwq + 1) << endl;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    int t = 1;
    // cin >> t;

    while (t--) {
        solve();
    }

    return 0;
}