import java.io.*; import java.util.*; import java.text.*; import java.math.*; import java.util.regex.*; public class Solution { public static void main(String[] args) { /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */ Scanner sc = new Scanner(System.in); int tests = sc.nextInt(); for(int t = 0; t < tests; t++) { BigInteger n = sc.nextBigInteger(), k = sc.nextBigInteger(); System.out.println(choose(n, k)); } } private static BigInteger choose_helper(BigDecimal c, BigInteger n, BigInteger cache_n_minus_i_plus_1, BigInteger i) { if (i.equals(BigInteger.ZERO)) return c.toBigInteger(); else return choose_helper( c.multiply(new BigDecimal(cache_n_minus_i_plus_1).divide(new BigDecimal(i))), n, cache_n_minus_i_plus_1.subtract(BigInteger.ONE), i.subtract(BigInteger.ONE)); } // n choose k: distinct subsets of k items chosen from n items public static BigInteger choose(BigInteger n, BigInteger k) { BigInteger low_k = n.subtract(k).min(k); return choose_helper(BigDecimal.ONE, n, n.subtract(k).add(BigInteger.ONE), n.subtract(k).min(k)); } }