[3-2] while문

■ while문

문장을 반복해서 수행해야 할 경우 while문을 사용한다. 그래서 while문을 반복문이라고도 부른다.

ex. 나무를 10번까지 찍으면 끝난다.
>>> treeHit = 0
>>> while treeHit < 10:
        treeHit = treeHit + 1
        print("i hit %d times." % treeHit)
        if treeHit == 10:
            print("finish!")
i hit 1 times.
i hit 2 times.
i hit 3 times.
i hit 4 times.
i hit 5 times.
i hit 6 times.
i hit 7 times.
i hit 8 times.
i hit 9 times.
i hit 10 times.
finish!

ex. 간단한 커피자판기
>>> coffee = 10
>>> money = 300
>>> while money:
        print("here you are")
        coffee = coffee - 1
        print("we have %d coffee." % coffee)
        if coffee == 0:
            print("sold out")
            break
here you are
we have 9 coffee
here you are
we have 8 coffee
here you are
we have 7 coffee
here you are
we have 6 coffee
here you are
we have 5 coffee
here you are
we have 4 coffee
here you are
we have 3 coffee
here you are
we have 2 coffee
here you are
we have 1 coffee
here you are
we have 0 coffee
sold out

ex. 실제 커피자판기 (금액 : 300원, 커피 잔량 : 10잔)
>>> coffee = 10
>>> while True:
        money = int(input("insert money"))
        if money == 300:
            print("here you are")
            coffee = coffee - 1
        elif money > 300:
            print("keep the change %d, here you are" % (money - 300))
            coffee = coffee - 1
        else:
            print("return money")
            print("we have %d coffee." % coffee)
        if coffee == 0:
            print("sold out")
            break
insert money["숫자 삽입"]
- 300 입력하면?
here you are
- 300 이상 입력하면?
keep the change 00, here you are
- 300 이하 입력하면?
return money['거스름돈']
we have 00 coffee.
- 10잔 다 팔리면?
sold out