public class MyClass {
static int factorial(int n) {
return (n==1 || n==0) ? 1 : n * factorial(n - 1);
}
public static void main(String args[]) {
int n = 7, r = 3;
int ncr = factorial(n) / (factorial(r) * factorial(n - r));
System.out.println(ncr);
}
}
/*
run:
35
*/