判断输入是偶数还是奇数

Question

你好，我正在尝试用Python写一个程序，这个程序会让用户输入一组1和0的数字。我希望这个程序能告诉我这些数字中有偶数个零、奇数个零，还是根本没有零。谢谢你的帮助！！

forstate = "start"
curstate = "start"
trans = "none"
value = 0


print "Former state....:", forstate
print "Transition....:", trans
print "Current state....", curstate
    while curstate != "You hav and even number of zeros":
        trans = raw_input("Input a 1 or a 0: ")
        if trans == "0" and value <2:
            value = value + 1
            forstate = curstate
        elif trans == "1" and value < 2:
            value = value + 0
            forstate = curstate
        curstate = str(value) + "  zeros"
        if value >= 2:
            curstate = "You have and even number of zeros"
        print "former state ...:", forstate
        print "Transition .....:", trans
        print "Current state....", curstate

Answer 1

try:
    inp = raw_input
except NameError:
    inp = input

zeros = sum(ch=='0' for ch in inp('Can I take your order? '))

if not zeros:
    print "none"
elif zeros%2:
    print "odd"
else:
    print "even"

当然可以！请把你想要翻译的内容发给我，我会帮你把它变得更简单易懂。

Answer 2

这听起来像是作业，或者更糟的是面试题，不过这会帮你入门。

def homework(s):
 counter = 0
 if '0' in s:
   for i in s:
     if i == '0':
       counter = counter + 1
 return counter

别忘了这部分哦

def odd_or_even_or_none(num):
  if num == 0:
    return 'This string contains no zeros'
  if num % 2 == 0
    return 'This string contains an even amount of zeros'
  else:
    return 'This string contains an odd amount of zeros'

如果你把作业叫出来，并给它一串数字，它会告诉你有多少个0

homework('101110101')

现在你知道了需要多少个0，就可以用这个数字去调用odd_or_even_or_none这个函数了

odd_or_even_or_none(23)

所以解决方案看起来是这样的

txt = input('Feed me numbers:  ')
counter = str( homework(txt) )
print odd_or_even_or_none(counter)

Answer 3

看起来你是在尝试做一个有限状态机？

try:
    inp = raw_input
except NameError:
    inp = input

def getInt(msg):
    while True:
        try:
            return int(inp(msg))
        except ValueError:
            pass

START, ODD, EVEN = range(3)
state_next = [ODD, EVEN, ODD]
state_str  = ['no zeros yet', 'an odd number of zeros', 'an even number of zeros']

state = START
while True:
    num = getInt('Enter a number (-1 to exit)')

    if num==-1:
        break
    elif num==0:
        state = state_next[state]

    print 'I have seen {0}.'.format(state_str[state])

编辑：

try:
    inp = raw_input
except NameError:
    inp = input

START, ODD, EVEN = range(3)
state_next = [ODD, EVEN, ODD]
state_str  = ['no zeros yet', 'an odd number of zeros', 'an even number of zeros']

def reduce_fn(state, ch):
    return state_next[state] if ch=='0' else state

state = reduce(reduce_fn, inp('Enter at own risk: '), START)
print "I have seen " + state_str[state]