Question one hundred and thirty-one: number of combinations

Description

Evaluate C (N, M), that is, find the number of combinations of N numbers in M number.

Input

The first line is a positive integer T (T <= 10), indicating that there are T groups of test data. Line 2 ~ Row T + 1 has two positive integers N, M (1 <= N, M <= 20 ).

Output

Input N, M in each group, and output a row. The row has a number, which is the C (N, M) value.

Sample Input

 

2
3 5
1 20

Sample Output

 

10

20

[Plain] # include <stdio. h>
 
_ Int64 fac (int );
 
Int main ()
{
Int num;
Int n;
Int m;
Scanf ("% d", & num );
 
While (num --)
{
Scanf ("% d", & n, & m );
 
Printf ("% d", fac (m)/fac (n)/fac (m-n ));

If (num> 0)
{
Printf ("\ n ");
}
}
 
Return 0;
}
 
_ Int64 fac (int)
{
Int I;
_ Int64 sum;
 
Sum = 1;
If (a = 0)
{
Sum = 1;
}
Else
{
For (I = 1; I <= a; I ++)
{
Sum * = I;
}
}
 
Return sum;
}

# Include <stdio. h>

_ Int64 fac (int );

Int main ()
{
Int num;
Int n;
Int m;
Scanf ("% d", & num );

While (num --)
{
Scanf ("% d", & n, & m );

Printf ("% d", fac (m)/fac (n)/fac (m-n ));

If (num> 0)
{
Printf ("\ n ");
}
}

Return 0;
}

_ Int64 fac (int)
{
Int I;
_ Int64 sum;

Sum = 1;
If (a = 0)
{
Sum = 1;
}
Else
{
For (I = 1; I <= a; I ++)
{
Sum * = I;
}
}

Return sum;
}