B.cpp

// Created by ahmed_drawy on 07/09/19.
/// Codeforces Round #580 (Div. 2)
#include <bits/stdc++.h>
#include <string.h>
#pragma clang diagnostic push
#pragma ide diagnostic ignored "OCUnusedMacroInspection"
using namespace std;
#define lp(i,start , end)       for(int i = start ; i<end ; ++i)
#define lllp(i,start , end)       for(ll i = start ; i<end ; ++i)
#define inN(arr ,  n) for(int i = 0 ; i< n ; ++i)  cin>>arr[i];
#define Rlp(i,start , end)      for(int i = start ; i>end ; --i)
#define all(v)                   ((v).begin(),(v).end())
#define sz(v)                  (int)((v).size())
#define clr(v,d)                memset(v , d , sizeof(v))
#define inf 0x3f3f3f3f
//#define dbg (v)    for(auto it : v)cout<<it<<' ';
typedef long long               ll;
typedef vector<int>             vi;
typedef vector  <ll>            vll;
typedef vector<vector<int> >    adj;
typedef pair<int ,int>          pii;
const double EPS =1e-7;
const int OO = 1e6;
#define endl '\n'
bool sortpair( const pair<int , int> & x, const pair<int , int> & y){
    return  x.first != y.first ? x.first < y.first : x.second > y.second ;
}
int dcomp(double x , double y){
    return fabs(x-y) <= EPS? 0: x>y?1:-1;
}
void smile() {
    ios_base::sync_with_stdio(0); cin.tie(NULL); cout.tie(NULL);
#ifndef ONLINE_JUDGE
    freopen("/home/tw3/Desktop/Desktop/training/in.txt", "r", stdin);
//    freopen("/home/tw3/Desktop/Desktop/training/out.txt" , "w" , stdout);
#endif
}
int main() {
    smile();
    int  n ;  cin  >> n ;

   ll ans = 0  , neg = 0 , zero =0; ;
   lp(i,0,n){
       ll x ;
       cin >>x;
        if(x <0 ){
           ans +=abs(x - (-1));
           neg++;
       }
       else if(x == 0 ){
           zero++;
       }
       else if(x >= 1) ans+=abs(x - 1);

   }
   if(neg &1){
       if(zero){
           cout << ans + zero;
       }
       else
            cout << ans +2 ;
   }
   else cout << ans + zero;
}