#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp> 
#include <ext/pb_ds/detail/standard_policies.hpp>
using namespace __gnu_pbds;
using namespace std;
#define getbit(n, i) (((n) & (1LL << (i))) != 0) 
#define setbit0(n, i) ((n) & (~(1LL << (i)))) 
#define setbit1(n, i) ((n) | (1LL << (i))) 
#define togglebit(n, i) ((n) ^ (1LL << (i))) 
#define lastone(n) ((n) & (-(n))) 
char gap = 32;
#define int long long
#define ll long long 
#define lll __int128_t
#define pb push_back
// #define double long double
#define pii pair<int,int>
typedef tree<
int,
null_type,
less<int>,
rb_tree_tag,
tree_order_statistics_node_update>
ordered_set;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
ll hashPrime = 1610612741;
typedef pair<double, double> pdd;
const double EPS = 1e-12;

const int N = 100006;
int ara[N];
void solve(){
    int n;
    cin>>n;
    n--;
    for(int i=0;i<n;i++){
        cin>>ara[i];
    }
    ara[0] = 1;

    bool hasZero = false;
    for(int i=0;i<n;i++) if(ara[i]==0) hasZero = true;
    if(!hasZero){
        cout<<"1\n";
        return;
    }
    int trailingZero = 0;
    for(int i=n-1;i>=0;i--){
        if(ara[i]==0) trailingZero++;
        else break;
    }

    if( !trailingZero ){
        cout<<2<<endl;
        return;
    }
    cout<<min(n, trailingZero+1)<<endl;

}
signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    cout << fixed << setprecision(10);
    solve();
    
    return 0;
}

/*
5
1 0 1 0
*/