//#include <bits/stdc++.h>
#include <iostream>
#include <iomanip>
#include <cmath>
#include <algorithm>
#include <climits>
#include <functional>
#include <cstring>
#include <string>
#include <cstdlib>
#include <ctime>
#include <cstdio>
#include <vector>
#include <stack>
#include <queue>
#include <deque>
#include <map>
#include <set>
#include <bitset>
#include <complex>
#include <random>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/priority_queue.hpp>
#define itn int
#define nit int
#define ll long long
#define ms multiset
#define F(i,a,b) for(register int i=a,i##end=b;i<=i##end;++i)
#define UF(i,a,b) for(register int i=a,i##end=b;i>=i##end;--i)
#define re register
#define ri re int
#define il inline
#define pii pair<int,int>
#define cp complex<double>
#define vi vector<int>
#define ull unsigned long long
#define mem0(x) memset(x,0,sizeof(x))
#define mem0x3f(x) memset(x,0x3f,sizeof(x))
using namespace std;
//using namespace __gnu_pbds;
const double Pi=acos(-1);
namespace fastIO {
	template<class T>
	inline void read(T &x) {
		x=0;
		bool fu=0;
		char ch=0;
		while(ch>'9'||ch<'0') {
			ch=getchar();
			if(ch=='-')fu=1;
		}
		while(ch<='9'&&ch>='0') x=(x*10-48+ch),ch=getchar();
		if(fu)x=-x;
	}
	inline int read() {
		int x=0;
		bool fu=0;
		char ch=0;
		while(ch>'9'||ch<'0') {
			ch=getchar();
			if(ch=='-')fu=1;
		}
		while(ch<='9'&&ch>='0') x=(x*10-48+ch),ch=getchar();
		return fu?-x:x;
	}
	template<class T,class... Args>
	inline void read(T& t,Args&... args) {
		read(t);
		read(args...);
	}
	char _n_u_m_[40];
	template<class T>
	inline void write(T x) {
		if(x==0){
			putchar('0');
			return;
		}
		T tmp = x > 0 ? x : -x ;
		if( x < 0 ) putchar('-') ;
		register int cnt = 0 ;
		while( tmp > 0 ) {
			_n_u_m_[ cnt ++ ] = tmp % 10 + '0' ;
			tmp /= 10 ;
		}
		while( cnt > 0 ) putchar(_n_u_m_[ -- cnt ]) ;
	}
	template<class T>
	inline void write(T x ,char ch) {
		write(x);
		putchar(ch);
	}
}
using namespace fastIO;
ll a[200002],pre[200002],suf[200002],t[200002],dp[200002],ans=1e18,n,c[200002];
inline void add(int pos,ll v){
	while(pos<=n){
		c[pos]=min(c[pos],v);
		pos+=(-pos&pos);
	}
}
inline ll query(int pos){
	ll rt=2000000000000000000ll;
	while(pos){
		rt=min(rt,c[pos]);
		pos-=(-pos&pos);
	}
	return rt;
}
inline void ins(int pos){
	add(lower_bound(t+1,t+n+1,pre[pos])-t,-2*pre[pos]+dp[pos]-pos);
}
inline void orz(int i){
	dp[i]=query(upper_bound(t+1,t+n+1,pre[i])-t-1)+pre[i]*2+i-1;//if(i==9)cerr<<dp[i]<<"K";
	if(a[i]<=0)dp[i]=min(dp[i],dp[i-1]);
	if(pre[i]>=0)dp[i]=min(dp[i],pre[i]+i-1);
	if(suf[i+1]>=0)ans=min(ans,dp[i]+max(0ll,n-i+suf[i+1]-1));
	if(i!=n)ins(i);
}
int main() {
	cin>>n;
	F(i,1,n)a[i]=read()-1;
	F(i,1,n)pre[i]=pre[i-1]+a[i];
	UF(i,n,1)suf[i]=suf[i+1]+a[i];
	if(pre[n]>=0)ans=n+pre[n]-1;
	memset(dp,0x3f,sizeof(dp));
	memset(c,0x3f,sizeof(c));
	dp[0]=0;
	F(i,1,n)t[i]=pre[i-1];
	sort(t+1,t+n+1);
	ins(0);
	F(i,1,n){
		orz(i);//cerr<<lower_bound(t+1,t+n+1,pre[i])-t<<" "<<dp[i]<<" "<<ans<<endl;
	}
	cout<<ans;
	return 0;
}