7660: [CSES Problem Set] Binomial Coefficients
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Description
Your task is to calculate nn binomial coefficients modulo $10^9+7$.
A binomial coefficient ${a \choose b}$ can be calculated using the formula $\frac{a!}{b!(a-b)!}$. We assume that $a$ and $b$ are integers and $0 \le b \le a$.
A binomial coefficient ${a \choose b}$ can be calculated using the formula $\frac{a!}{b!(a-b)!}$. We assume that $a$ and $b$ are integers and $0 \le b \le a$.
Input
The first input line contains an integer $n$: the number of calculations.
After this, there are $n$ lines, each of which contains two integers $a$ and $b$.
After this, there are $n$ lines, each of which contains two integers $a$ and $b$.
Output
Print each binomial coefficient modulo $10^9+7$.
Constraints
$1≤n≤10^5$
$0 \le b \le a \le 10^6$
$0 \le b \le a \le 10^6$
Sample 1 Input
3
5 3
8 1
9 5
Sample 1 Output
10
8
126