19th Candies and Two Sisters

a.题目链接

Problem - 1335A - Codeforces

b.我的题解

#include <iostream>
using namespace std;
int main()
{
	int t;
	for(cin >> t; t--; ){
        int a;
	    cin >> a;
	    cout << (a-1) - a/2 <<endl;	
    }
	return 0;
}

// 数学题，比较简单的