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

142 Views Asked by At

I'm new to python, I am doing the TWO + TWO = FOUR, where each letter represents a different number from 1-10. I need to find all combinations. I was wondering if there is a better way to write it, especially 'if' and '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)

I've tried writing it like this but it gave me more than 7 results

if 2*(t*100 + w*10 + o) == f*1000 + o*100 + u*10 + r and t != f != w != o != u != r
3

There are 3 best solutions below

1
lenik On BEST ANSWER

Work smart, not hard =)

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)

This will save you a lot of unnecessary iterations.

0
ExplodingGayFish On

You could use a simple hack like this:

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)

The idea is set only stores distinct numbers, so if they are pair-wise different then the length of the set should be equal to the number of variables

2
o11c On

You can use 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)):

If you don't want to repeat all the ranges you can do:

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

but honestly that's less readable.