def combination(setSize, combinationSize):
    """
    Computes the number of k-combinations in a set
    Source : https://python.jpvweb.com/python/mesrecettespython/doku.php?id=combinaisons
    :param setSize: number of elements in the set
    :param combinationSize: number of elements in a combination
    :return: number of k-combinations
    """
    if combinationSize > setSize // 2:
        combinationSize = setSize - combinationSize
    x = 1
    y = 1
    i = setSize - combinationSize + 1
    while i <= setSize:
        x = (x * i) // y
        y += 1
        i += 1
    return x