There are two sisters Alice and Betty. You have $n$ candies. You want to distribute these $n$ candies between two sisters in such a way that:

• Alice will get $a$ ($a > 0$) candies;
• Betty will get $b$ ($b > 0$) candies;
• each sister will get some integer number of candies;
• Alice will get a greater amount of candies than Betty (i.e. $a > b$);
• all the candies will be given to one of two sisters (i.e. $a+b=n$).

Your task is to calculate the number of ways to distribute exactly $n$ candies between sisters in a way described above. Candies are indistinguishable.

Formally, find the number of ways to represent $n$ as the sum of $n=a+b$, where $a$ and $b$ are positive integers and $a>b$.

You have to answer $t$ independent test cases.

The first line of the input contains one integer $t$ ($1 \le t \le 10^4$) — the number of test cases. Then $t$ test cases follow.

The only line of a test case contains one integer $n$ ($1 \le n \le 2 \cdot 10^9$) — the number of candies you have.

For each test case, print the answer — the number of ways to distribute exactly $n$ candies between two sisters in a way described in the problem statement. If there is no way to satisfy all the conditions, print $0$.