But that's what my solution did. The problem is that that solution doesn't evaluate things like (4+4)×(4+4)-4
Regards, Elias On 25 January 2017 at 09:49, <[email protected]> wrote: > > op ← '+-x÷' > > i meant a brute force creating a HUGE matrix '(((4 op[⍳4] 4) > op[⍳4] 4) op[⍳4] 4) op[⍳4] 4' > > > > > > On Wed, 25 Jan 2017 08:49:37 +0800 > Elias Mårtenson <[email protected]> wrote: > > > Thanks, but the code I included already gives me that solution, so that > was > > never the problem. > > > > The issue here is more one of trying to come up with a good APL > solution. I > > really don't like mine, it's too verbose. > > > > Regards, > > Elias > > > > On 25 Jan 2017 8:46 AM, <[email protected]> wrote: > > > > > since no one has responded yet this is my best guess without pure > random > > > code testing from array of chars following your rules > > > > > > the answer is : ⍎'(((4+4)x4)-4)÷4' ;) > > > i think the problem is from an episode of cartalk ?? > > > > > > > > > > > > On Tue, 24 Jan 2017 23:47:10 +0800 > > > Elias Mårtenson <[email protected]> wrote: > > > > > > > My daughter had this maths problem, and quote it from memory: > > > > > > > > Given five 4's, separated by the mathematical functions +, -, × and ÷ > > > form > > > > the number 7. The problem also allowed her to use parentheses. > > > > > > > > I decided to write an APL expression to solve this, and this is what > I > > > came > > > > up with: > > > > > > > > > > > > * d ← {⍵÷⍺}* > > > > * (↑¨ 7 = ⍎¨ v) / v ← {"4 " , ↑,/ {{⍵," 4 "}¨⍵} ⍵}¨ ,↑∘.,/4 ⍴ > ⊂'+-×d'* > > > > > > > > Now, this program finds two solutions, which is good enough for me. > > > > However, my program doesn't find solutions that require parentheses. > > > > > > > > Problem 1: Can anyone simplify my program? > > > > Problem 2: Can anyone come up with a solution that also checks for > > > > parentheses? > > > > > > > > Regards, > > > > Elias > > > > > > > >
