#include <bits/stdc++.h>
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;
typedef long long ll;
typedef pair<int,int> P;
const int INF = 1e9;
const int MOD = 1000000007;

int main(){
    int n;
    cin >> n;
    vector<int> a(n);
    rep(i,n) cin >> a[i];
    int ans = 0;
    vector<P> k = {P(a[0],0)};
    rep(i,n){
        if(k.back().first == a[i]){
            k.back().second ++;
        }else{
            k.emplace_back(P(a[i],1));
        }
    }

    bool ok = true;
    for(P p:k){
        if(p.second > 1) ans += p.second - 1;
        else{
            if(ok){
                ans ++;
                ok = false;
            }else{
                ok = true;
            }
        }
    }

    cout << ans << endl;

    return 0;
}