#include<bits/stdc++.h>
using namespace std;
int main(){

	int t;
	cin >> t;

   

	while(t--){
		int count = 0;
		int n;
		cin >> n;
        
		for(int i=1,j=n-1; i<n/2, j>n/2; i++,j--){
			if(i+j == n){
				count++;
			}
		}
		cout << count << endl;
	}
	
	

	
}