1335A.cpp

//HHM
// DATE: 29-06-2022
//TIME:19:54:10
 
#include <bits/stdc++.h>
using namespace std;
 
#define ll long long int
#define dbl double
#define deb(v) cout << #v << " " << v << "\n"
#define deb2(v, k) cout << #v << " " << v << "\n" \
                        << #k << " " << k << "\n"
#define vin(name,size)         \
    for (i = 0; i<size ;i++)\
    cin>>name[i]
#define vout(name)                   \
    for (i = 0; i<name.size();i++)   \
    cout<<name[i]<<" ";              \
    cout << endl
#define vec(type1, name) vector<type1> name
#define vp(type1, type2, name) vector<pair<type1, type2>> name
#define st(type, name) set<type> name
#define mpp(type1, type2, name) map<type1, type2> name
#define pb push_back
#define MP make_pair
#define F first
#define S second
#define all(x) x.begin(), x.end()
#define part(x, a, b) x.begin() + a, x.begin() + b
#define Pi 3.1415926535897932384626
ll power(ll a,ll b){
    ll res=1;
    for(ll i=1;i<=b;i++)res*=a;
     return res;
}
void HHM()
{
    ll i, j, k;
    ll n;
    cin >> n;
    cout<<(n-1)/2<<"\n";
     //set<ll>st;
     //map<ll,ll>mp;
     //string s;cin>>s;
     //vector<ll>v(n,0);

    return;
}
 
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    
    ll t = 1;
    cin >> t;
    //ll tt=1;     
    while (t--)
    {
      //cout << "Case #" << tt << ": ";
        HHM();
      //tt++;;
    }
}
//freopen("input.txt", "r", stdin);
//freopen("output.txt", "w", stdout);