#include<bits/stdc++.h>
using namespace std;

#define ll long long
#define cl(a) memset(a,0,sizeof a)
#define copy(a,b) copy(begin(a),end(a),begin(b))
#define ld long double
#define dot(x) fixed<<setprecision(x)
#define foru(a,b,c) for(ll a=b;a<=c;a++)

ll n,a[100050],cnt;
bool flg[100050];

int main(){
    freopen("bzoj_4300.in","r",stdin);
    freopen("bzoj_4300.out","w",stdout);
    cin>>n;
    for(ll i=1;i<=n;i++){
        cin>>a[i];
    }
    for(ll i=2;i<=n;i++){
        if(a[i]&a[i-1]){
            flg[i]=flg[i-1]=1;
        }
    }
    for(ll i=1;i<=n;i++){
        if(flg[i]){
            cnt++;
        }
    }
    cout<<cnt;
    return 0;
}