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CF1335A.Candies and Two Sisters
Candies and Two Sisters
There are two sisters Alice and Betty. You have candies. You want to distribute these candies between two sisters in such a way that:
- Alice will get () candies;
- Betty will get () candies;
- each sister will get some integer number of candies;
- Alice will get a greater amount of candies than Betty (i.e. );
- all the candies will be given to one of two sisters (i.e. ).
Your task is to calculate the number of ways to distribute exactly candies between sisters in a way described above. Candies are indistinguishable.
Formally, find the number of ways to represent as the sum of , where and are positive integers and .
You have to answer independent test cases.
Input
The first line of the input contains one integer () — the number of test cases. Then test cases follow.
The only line of a test case contains one integer () — the number of candies you have.
Output
For each test case, print the answer — the number of ways to distribute exactly candies between two sisters in a way described in the problem statement. If there is no way to satisfy all the conditions, print .
Note
For the test case of the example, the possible ways to distribute candies are:
- , ;
- , ;
- , .
Samples
6
7
1
2
3
2000000000
763243547
3
0
0
1
999999999
381621773
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