def apply_percentage(quantity, percentage):
    return quantity * percentage/100

def lustrum (year1, year2):
    return (year2-year1) // 5

def salaries(sfix, sales, percentage, bonus, year_s, year_p):
    svar1 = apply_percentage (sales, percentage)
    num_lustrum = lustrum (year_s, year_p)
    svar2 = num_lustrum * bonus
    return sfix + svar1 + svar2