#include<bits/stdc++.h>
#include<iostream>
#include<cstring>
#include<cmath>
#include<algorithm>
using namespace std;
#define ll long long 
#define fo(i,n) for(i=0;i<n;i++)
ll i,n;
 
 
bool checkperfectsquare(ll n){
    if (ceil((double)sqrt(n)) == floor((double)sqrt(n)))return true;
        else return false;}
 
vector<ll> divisorsofanum(ll num){//sqrt n complexity
     vector<ll> v;
     for(ll i = 2; i < sqrt(num);i++){
        if(num%i == 0){v.push_back(i);v.push_back(num/i); }}
        if(checkperfectsquare(num) == 1)v.push_back(sqrt(num));
     return v;}
 


 
 
 
void solve(){
ll n;
cin >> n;
ll arr[n];
ll even = 0;
ll odd = 0;
for(i =0 ; i < n;i++){cin >> arr[i];
arr[i] = arr[i]%2;
if(arr[i]%2 == 0)even++;
else odd++;

}
if(abs(even-odd) >1){
    cout << -1;
    return;
}

vector<pair<ll,ll>> v;

ll arr2[n];
for(i =0 ;  i < n;i++){
    arr2[i] = arr[i];
}
ll steps1 = 0,steps2 = 0;
for(i = 1 ; i < n ;i++){
    
    
    if(arr[i] != arr[i-1])continue;
    else {
        if(i == n-1){steps1= INT_MAX;break;}
        ll j;
        
        for(j = i ;j < n;j++){
            if(arr[j] != arr[i])break;
        }
        ll k = j;
        
        for(j = k ;j >= i + 1;j--){
        swap(arr[j],arr[j-1]);
        steps1++;
    }
    }
    
   

    

}



for(i =0 ; i < n;i++){arr[i] = arr2[i];}


for(i = n - 1 ; i >= 1;i--){
    
    if(arr[i] != arr[i-1]){continue;}
    else {
        if(i == 1){steps2 = INT_MAX;break;}
        ll j;
        for(j = i - 1 ;j > -1;j--){
            if(arr[j] != arr[i])break;
        }
        ll k = j;
        
        
        for(j = k + 1 ;j < i ;j++){
        swap(arr[j],arr[j-1]);
        steps2++;
    }
    }
    
   

    

}



cout << min(steps2,steps1);
    

}
 
 
 
 
int main(){
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
int t=1;
cin>>t;
while(t--){
    solve();
 cout << endl;
}
 
}