tallet.py

"""
E=7
TALLET +
SIGNAL
------
ELAINE

"""
letters = set('T A L L E T S I G N A L E L A I N E'.split())
assoc = {letter: None for letter in letters}
assoc['E'] = 7

def number_from_letters(letters, assoc):
    return sum(10**power*assoc[letter] for (power, letter) in enumerate(reversed(letters)))

def ok(assoc):
    return len(set(assoc.values())) == len(assoc) and (number_from_letters('TALLET', assoc) + number_from_letters('SIGNAL', assoc) == number_from_letters('ELAINE', assoc))

def solve(assoc):
    available_digits = reversed(tuple(set(range(0, 10)) - set(assoc.values())))
    for letter in assoc:
        if assoc[letter] is None:
            for digit in available_digits:
                assoc[letter] = digit
                if solve(assoc):
                    return assoc
                assoc[letter] = None                
    return assoc if (not None in assoc.values()) and ok(assoc) else False
        
if __name__ == '__main__':
    result = solve(assoc)
    print(result)
    print(number_from_letters('TALLET', assoc))
    print(number_from_letters('SIGNAL', assoc))
    print(number_from_letters('ELAINE', assoc))