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#include <iostream>
#include <vector>
#include <cstring>
using namespace std;
vector<pair<int, int> > g[2005];
int n;
int dp[2005][4100];
int rec(int at, int prev_number) {
    if(at == n) {
        return 0;
    }
    if(dp[at][prev_number] != -1) {
        return dp[at][prev_number];
    }
    int result = 2e9;
    for(int i = 0; i < (int) g[at].size(); i++) {
        int number = g[at][i].first;
        if(prev_number <= number) {
            result = min(result, rec(at + 1, number) + g[at][i].second);
        }
    }
    return dp[at][prev_number] = result;
}
int main()
{
    ios_base::sync_with_stdio(false);
    cin >> n;
    memset(dp, -1, sizeof dp);
    for(int i = 0; i < n; i++) {
        int x;
        cin >> x;
        
        for(int number = 0; number < (1 << 12); number++) {
            if(__builtin_popcount(number) == __builtin_popcount(x)) {
                g[i].push_back(make_pair(number, __builtin_popcount(number ^ x) / 2));
                
            }
        }
    }
    cout << rec(0, 0) << endl;
    return 0;
}