ICPC NWERC 2011 A - Binomial Coefficients
View as PDFGunnar is quite an old and forgetful researcher. Right now he is writing a paper on security in social networks and it actually involves some combinatorics. He wrote a program for calculating binomial coefficients to help him check some of his calculations.
A binomial coefficient is a number
where  and 
 are non-negative integers.
Gunnar used his program to calculate  and got a number 
 as a result. Unfortunately, since he is forgetful, he forgot the numbers 
 and 
 he used as input. These two numbers were a result of a long calculation and they are written on one of many papers lying on his desk. Instead of trying to search for the papers, he tried to reconstruct the numbers 
 from the output he got. Can you help him and find all possible candidates?
Input Specification
On the first line a positive integer: the number of test cases, at most .
After that, per test case: one line with an integer  
: the output of Gunnar's program.
Output Specification
Per test case:
- one line with an integer: the number of ways of expressing 
as a binomial coefficient.
 - one line with all pairs 
that satisfy
. Order them in increasing order of
and, in case of a tie, order them in increasing order of
. Format them as in the sample output.
 
Sample Input
2
2
15
Sample Output
1
(2,1)
4
(6,2) (6,4) (15,1) (15,14)
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