妈，我真服

都不要忘记0，它也收“翻转费”

#include <bits/stdc++.h>
using namespace std;
int main(){
    int n,cnt = 0,z = 0;
    long long sum = 0;
    vector<long long> a;
    cin >>n;
    while(n--) {
        long long v;
        cin >> v;
        a.push_back(v);
    }
    for (int i=0;i<a.size();i++){
        long long num = a[i];
        if (num > 0)
            sum = sum + (num - 1);
        else if (num == 0){
            z++;
            sum++;
        }else{
            sum = sum + abs(num - (-1));
            cnt++;
        }
    }if (cnt % 2 != 0 && z == 0)
        sum+=2;
    cout << sum;
    return 0;