/// Data type used by combinatorics functions
typedef unsigned long long int largeint;

// Function prototypes or function declarations:

/// Returns the number of combinations of r elements that can be made out of n elements
largeint combinations(largeint n, largeint r);

/// Returns n!
largeint factorial(largeint n);

/// Evaluates as the min value between a and b
#define min(a, b) ((a) < (b) ? (a) : (b))

/// Evaluates as the max value between a and b
#define max(a, b) ((a) > (b) ? (a) : (b))