在Python中是否有不同的写多个条件的方法？

Question

我是 python 的新手，我正在做 TWO + TWO = FOUR，其中每个字母代表 1-10 之间的不同数字。我需要找到所有组合。想知道有没有更好的写法，尤其是'if'和'for'

for t in range (1,10):
  for f in range (1,10):
    for w in range(10):
      for o in range(10):
        for u in range(10):
          for r in range(10):
            if 2*(t*100 + w*10 + o) == f*1000 + o*100 + u*10 + r and t is not f and t is not w and t is not o and t is not u and t is not r and f is not w and f is not o and f is not o and f is not u and f is not r and w is not o and w is not u and w is not r and o is not u and o is not r and u is not r:
              print(t,w,o, "and", f,o,u,r)

我试过这样写，但它给了我超过 7 个结果

if 2*(t*100 + w*10 + o) == f*1000 + o*100 + u*10 + r and t != f != w != o != u != r

Answer 1

您可以使用这样的简单技巧：

for t in range (1,10):
  for f in range (1,10):
    for w in range(10):
      for o in range(10):
        for u in range(10):
          for r in range(10):
            if 2*(t*100 + w*10 + o) == f*1000 + o*100 + u*10 + r and len(set([t,f,w,o,u,r])) == 6:
              print(t,w,o, "and", f,o,u,r)

想法是 set 只存储不同的数字，所以如果它们成对不同，那么集合的长度应该等于变量的数量

Answer 2

您可以使用 itertools.product:

for t, f, w, o, u, r in itertools.product(range(1, 10), range(1, 10), range(10), range(10), range(10), range(10)):

如果你不想重复所有 ranges 你可以这样做：

for t, f, w, o, u, r in itertools.product(*([range(1, 10)]*2 + [range(10)]*4)):

但老实说，可读性较差。

Answer 3

聪明地工作，不努力 =)

for t in range (1,10):
  for f in range (1,10):
    if f == t : continue
    for w in range(10):
      if w in [t,f] : continue
      for o in range(10):
        if o in [t,f,w] : continue
        for u in range(10):
          if u in [t,f,w,o] : continue
          for r in range(10):
            if r in [t,f,w,o,u] : continue
            if 2*(t*100 + w*10 + o) == f*1000 + o*100 + u*10 + r :
              print(t,w,o, "and", f,o,u,r)

这将为您节省很多不必要的迭代。

在Python中是否有不同的写多个条件的方法？

Is there a different way to write multiple conditions in Python?

python

python-3.x

cryptarithmetic-puzzle