페어코딩6: 부족한 금액 채우기

# 부족한 금액 계산하기
"""""
성우님
def solution(price, money, count):
    answer = 0
    num = 0
    pricecount = 0
    while num < count:
        num += 1
        pricecount += price * num
    answer += pricecount - money
    if money < pricecount:
        return answer
    elif money >= pricecount:
        return 0
print(solution(3,20,4))
"""


"""
재준님
def solution(price, money, count):
    answer = -1
    sum_price = 0
    for i in range(1,(count+1)):
        sum_price += price*i
        if sum_price > money:
            answer=sum_price-money
        else:
            answer=0
    return answer

    while count > 1:
"""