So I was recentlr solving a codeforces question and came across this code:

#include<bits/stdc++.h>
#define ll              long long
#define ull             unsigned long long
#define pb              push_back
#define fastread()      (ios_base:: sync_with_stdio(false),cin.tie(NULL));
using namespace std;
int main()
{
    fastread();
    int n,a[100001];
    ll sum = 0;
    int pos = 0,neg = 0,zero = 0,k = 0;
    cin>>n;
    for(int i=0; i<n; i++){
        cin>>a[i];
    }
    //sort(a,a+n);
 
    for(int i=0; i<n; i++){
        if(a[i] == 1 || a[i] == -1)continue;
        else if(a[i] < -1){
            sum += abs(a[i] + 1);
            a[i] -= (a[i] + 1);
        }
        else if( a[i] > 1){
            sum += a[i] - 1;
            a[i] = 1;
        }
 
    }
    for(int i=0; i<n; i++){
        if(a[i] == 0){
            zero++;
            a[i] = 1;
        }
        else if(a[i] == -1)neg++;
        else if(a[i] == 1)pos++;
    }
    sum += zero;
    pos += zero;
    //zero = 0;
    if(neg % 2 == 1){
        if(zero > 0)pos--;
        else sum+=2;
    }
 
    cout<<sum<<endl;
}

the code runs at about 77 ms, and this was my code:

#include<bits/stdc++.h>
#define ll              long long
#define ull             unsigned long long
#define pb              push_back
#define fastread()      (ios_base:: sync_with_stdio(false),cin.tie(NULL));
using namespace std;
 
int main()
{
    fastread();
    int n,m(0),p(1),z(0);
    ll ans(0);
    cin >> n;
 
    int arr[n];
 
    for(int i = 0; i < n; i++){
        cin >> arr[i];
 
        if(arr[i] == 1 || arr[i] == -1){
            ans = ans + 0;
        }else if(arr[i] == 0){
            arr[i] = arr[i]++;
            ans++;
            //cout << ans << " ";
        }else{
            if(arr[i] < 0){
                ans += abs(arr[i]) - 1;
                arr[i] = -1;
                //cout << ans << " " << arr[i];
            }else{
                ans += abs(arr[i]) - 1;
                arr[i] = 1;
                //cout << ans << " ";
            }
        }
 
        p = arr[i] * p;
        //cout << p << endl;
    }
 
 
   if(p < 0){
        cout << ans + 2;
    }else{
        cout << ans;
    }
}

I wanted to optimize the first code which has two loops so I only used one but my program has an execution time of 78 ms, any reasons why decreasing the loop still resulted in more time consumption.