def cardAmount(i) :

    if i < 0 : return "invalid" 
    else : return int(2 * (i) + (3 * ((i-1) * (i) / 2)))

print(cardAmount(4))

print((1*(3 * 1+1) // 2))

print("adsjfkş".isdigit())


s=sorted("hello")

print(s)