#include <bits/stdc++.h>
#define FOR(v, a, b) for(int v = (a); v < (b); ++v)
#define FORE(v, a, b) for(int v = (a); v <= (b); ++v)
#define REP(v, n) FOR(v, 0, n)
#define REPE(v, n) FORE(v, 0, n)
#define REV(v, a, b) for(int v = (a); v >= (b); --v)
#define ALL(x) (x).begin(), (x).end()
#define ITR(it, c) for(auto it = (c).begin(); it != (c).end(); ++it)
#define RITR(it, c) for(auto it = (c).rbegin(); it != (c).rend(); ++it)
#define EXIST(c,x) ((c).find(x) != (c).end())
#define LLI long long int
#define fst first
#define snd second
#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif
#ifndef M_E
#define M_E 2.71828182845904523536
#endif
#ifdef DEBUG
#include <boost/core/demangle.hpp>
#define dump(x) cerr << "L" << __LINE__ << ": in " << __PRETTY_FUNCTION__ << " \e[32;1m" << boost::core::demangle(typeid(x).name()) << "\e[37m" << " " << (#x) << " = " << (x) << "\e[m" << endl;
#else
#define dump(x)
#endif
#define pln(x) cout << (x) << endl
#define gcd __gcd

using namespace std;
template <class T> constexpr T lcm(T m, T n){return m/gcd(m,n)*n;}

template <typename T> using V = vector<T>;
template <typename T, typename U> using P = pair<T,U>;
template <typename I> void join(ostream &ost, I s, I t, string d=" "){for(auto i=s; i!=t; ++i){if(i!=s)ost<<d; ost<<*i;}ost<<endl;}
template <typename T> istream& operator>>(istream &is, vector<T> &v){for(auto &a : v) is >> a; return is;}
template <typename T, typename U> istream& operator>>(istream &is, pair<T,U> &p){is >> p.first >> p.second; return is;}

template <typename Iter> ostream& out_container(ostream &os, Iter first, Iter last){
  os << "{"; auto itr = first; while(itr != last){if(itr != first) os << ","; os << *itr; ++itr;} os << "}"; return os;
}

template <typename T> ostream& operator<<(ostream &os, const vector<T> &c){return out_container(os,ALL(c));}
template <typename T> ostream& operator<<(ostream &os, const deque<T> &c){return out_container(os,ALL(c));}
template <typename T> ostream& operator<<(ostream &os, const set<T> &c){return out_container(os,ALL(c));}
template <typename T> ostream& operator<<(ostream &os, const unordered_set<T> &c){return out_container(os,ALL(c));}
template <typename T, typename U> ostream& operator<<(ostream &os, const map<T,U> &c){return out_container(os,ALL(c));}
template <typename T, typename U> ostream& operator<<(ostream &os, const unordered_map<T,U> &c){return out_container(os,ALL(c));}
template <typename T, typename U> ostream& operator<<(ostream& os, const pair<T,U> &p){os << "(" << p.first << "," << p.second << ")"; return os;}

template <typename T, typename U> T& chmin(T &a, const U &b){return a = (a<=b?a:b);}
template <typename T, typename U> T& chmax(T &a, const U &b){return a = (a>=b?a:b);}
template <typename T, size_t N, typename U> void fill_array(T (&a)[N], const U &v){fill((U*)a, (U*)(a+N), v);}

//LLI dp[101000][3];

int main(){
  cin.tie(0);
  ios::sync_with_stdio(false);

  LLI L;
  while(cin >> L){
    vector<LLI> A(L); cin >> A;

    LLI s = accumulate(ALL(A), 0LL);

    vector<LLI> sum(L+1);
    REP(i,L) sum[i+1] = sum[i] + A[i];
    
    //fill_array(dp,1e9);

    vector<vector<LLI>> dp(201000, vector<LLI>(3, 1e18));

    vector<LLI> B(L), C(L);
    REP(i,L){
      if(A[i] == 0){
	B[i] = 1;
	C[i] = 2;
      }else{
	B[i] = (A[i]%2?0:1);
	C[i] = (A[i]%2?1:0);
      }
    }
    
    dp[0][0] = 1;
    dp[0][1] = dp[0][2] = 2;
    
    REP(i,L){
      chmin(dp[i+1][0], min({sum[i]+B[i], dp[i][0]+B[i], dp[i][1]+B[i]}));
      chmin(dp[i+1][1], min({sum[i]+C[i], dp[i][1]+C[i]}));
      chmin(dp[i+1][2], min({sum[i]+C[i], dp[i][0]+C[i], dp[i][1]+C[i], dp[i][2]+C[i]}));
      dump(dp[i+1][1]);
    }

    LLI ans = 1e18;

    chmin(ans, s);
    
    FORE(i,1,L){
      LLI t = min({dp[i][0], dp[i][1], dp[i][2]}) + s-sum[i];
      //dump(t);
      chmin(ans, t);
    }
    cout << ans << endl;
  }
  
  return 0;
}


Measured memory_bytes: 17536