#include <bits/stdc++.h>
using namespace std;
#define ll long long

int main()
{
    int t;
    cin >> t;
    while(t--){
        ll n;
        cin >> n;
        
        map<ll, int>mp;
        for(int i = 1; i < n; i++){
            mp[i]++;
        }
        int cnt = 0;
        for(int i = 1; i < n; i++){
            ll req = n - i;
            
            if(i < req and mp.find(req) != mp.end()){
                cnt++;
            }
        }
        cout << cnt << '\n';
    }

    return 0;
}