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Solving a crypto-arithmetic puzzle with a relational database

Say you are given a crypto-arithmetic puzzle:

SEND + MORE = MONEY

The goal is to substitute numbers (0-9) for the letters so that addition is done.

I understand how to mathematically approach the problem, but I'm not sure how to solve this with a relational database.

How should a circuit be designed to solve this problem?

What will the SQL query look like that will try to solve this problem?

EDIT: There are some limitations:

  • The same number should be used for a given letter. For example, if you assume "5" for the letter E, then E should get the value "5" in all places where it occurs.
  • Different letters must have different numbers, for example, you cannot assign “4” to both E and M.
  • None of the numbers (words) can have any leading zeros
+5
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2 answers

This answers another problem set by the user.

SEND + MORE = MONEY, where each character has a unique number and not a word starts from scratch.

select
    top 1
    S.num as S,
    E.num as E,
    N.num as N,
    D.num as D,
    M.num as M,
    O.num as O,
    R.num as R,
    Y.num as Y,
    (S.num * 1000 + E.num * 100 + N.num * 10 + D.num) as [SEND],
    (M.num * 1000 + O.num * 100 + R.num * 10 + E.num) as MORE,
    (S.num * 1000 + E.num * 100 + N.num * 10 + D.num) + (M.num * 1000 + O.num * 100 + R.num * 10 + E.num) as SEND_plus_MORE,
    (M.num * 10000 + O.num * 1000 + N.num * 100 + E.num * 10 + Y.num) as [MONEY]

from
    Digits as S
    join digits as E on E.num <> S.num
    join digits as N on N.num <> S.num and N.num <> E.num
    join digits as D on D.num <> S.num and D.num <> E.num and D.num <> N.num
    join digits as M on M.num <> S.num and M.num <> E.num and M.num <> N.num and M.num <> D.num
    join digits as O on O.num <> S.num and O.num <> E.num and O.num <> N.num and O.num <> D.num and O.num <> M.num
    join digits as R on R.num <> S.num and R.num <> E.num and R.num <> N.num and R.num <> D.num and R.num <> M.num and R.num <> O.num
    join digits as Y on Y.num <> S.num and Y.num <> E.num and Y.num <> N.num and Y.num <> D.num and Y.num <> M.num and Y.num <> O.num and Y.num <> R.num

where
    (S.num * 1000 + E.num * 100 + N.num * 10 + D.num)
    + (M.num * 1000 + O.num * 100 + R.num * 10 + E.num)
    = (M.num * 10000 + O.num * 1000 + N.num * 100 + E.num * 10 + Y.num)     
    and S.num <> 0 and M.num <> 0

I was thinking of something in the WHERE clause to provide unique numbers, but I believe this ends up processing too many permutations before the WHERE clause is checked.

Since we are dealing with only 10 digits, I think that it is best to create sentences with a long ON, and not for speed.

FROM + WHERE ON. .

from
    Digits as S
    cross join digits as E
    cross join digits as N
    cross join digits as D
    cross join digits as M
    cross join digits as O
    cross join digits as R
    cross join digits as Y

where
    (S.num * 1000 + E.num * 100 + N.num * 10 + D.num)
    + (M.num * 1000 + O.num * 100 + R.num * 10 + E.num)
    = (M.num * 10000 + O.num * 1000 + N.num * 100 + E.num * 10 + Y.num)     
    and S.num <> 0 and M.num <> 0

        and (select max(B.Count) from   
                (select COUNT(*) as Count from 
                    (select S.num, 's' as letter   -- the letters are included to make sure the unions do not merge equivalent rows
                    UNION select E.num, 'e'
                    UNION select N.num, 'n'
                    UNION select D.num, 'd'
                    UNION select M.num, 'm'
                    UNION select O.num, 'o'
                    UNION select R.num, 'r'
                    UNION select Y.num, 'y') as A
                    group by A.num
                ) as B
             ) = 1
+6

.

: OVER + FLOW = STACK, , 10

  • , , OVER + FLOW + STACK, .

- , Digits , earch 1 9 ( 0 9, ).

- , , .

select
    top 5 
    O.num as O,
    V.num as V,
    E.num as E,
    R.num as R,
    F.num as F,
    L.num as L,
    W.num as W,
    S.num as S,
    T.num as T,
    A.num as A,
    C.num as C,
    K.num as K,
    (O.num * 1000 + V.num * 100 + E.num * 10 + R.num) as [OVER],
    (F.num * 1000 + L.num * 100 + O.num * 10 + W.num) as FLOW,
    (O.num * 1000 + V.num * 100 + E.num * 10 + R.num) + (F.num * 1000 + L.num * 100 + O.num * 10 + W.num) as OVER_plus_FLOW,
    (S.num * 10000 + T.num * 1000 + A.num * 100 + C.num * 10 + K.num) as STACK
from
    Digits as O
    cross join digits as V
    cross join digits as E
    cross join digits as R
    cross join digits as F
    cross join digits as L
    cross join digits as W
    cross join digits as S
    cross join digits as T
    cross join digits as A
    cross join digits as C
    cross join digits as K
where
    (O.num * 1000 + V.num * 100 + E.num * 10 + R.num)
    + (F.num * 1000 + L.num * 100 + O.num * 10 + W.num)
    = (S.num * 10000 + T.num * 1000 + A.num * 100 + C.num * 10 + K.num)

, . 5, :

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0, ( ).

Digits

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+4

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