Python正则表达式：遍历键以查找完全匹配

Question

I am trying to find the exact match of a certain string:

The user is prompted to enter a string, say 'AAAA' and I want to find the exact instants that this key is in a certain dictionary, dict that looks like {'AAAA':1, 'ZZZZ':2, 'BCBC':3}

Right now i have:

string = input("enter string")
for key in dict.keys():
    regex = re.compile(r'^(key)$')
    if re.search(regex, string):
        match = re.search(string)
        print('match at %s') % (match.group(0))

I want the user to input a string, then to loop through all the possible keys and see if there's an exact match. If there is an exact match, I want to return the value (the index) where that key is. Hence, if a user inputs AAAAZZZZ, I want it to print (1,2)

Answer 1

I would not use regexp for this case but just look through the possible keys:

d = {'AAAA':1, 'ZZZZ':2, 'BCBC':3}

k = 'AAAAZZZZ'

result = []
start_index = 0
for index in range(0, len(k)+1):
    if k[start_index:index] in d:
        result.append(d[k[start_index:index]])
        start_index = index

print(result)

Answer 2

Sorry if my python is a bit rusty, but you should just store the indices you want and combine them after the loop.

Note: this is probably not the most efficient way to go about this, but won't be terrible given a small dictionary.

string = input("enter string")
indices = []
for key in dict.keys():
    regex = re.compile(r'^(key)$')
    if re.search(regex, string):
        match = re.search(string)
        indices.append(dict[key])

print(','.join(map(str, indices)))