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output formatting - Format something Inactive


ops = Map[Inactive, 

Tuples[{Times, Plus, Subtract, Divide}, {4 - 1}], {2}];

rules = Thread[{a, b, c} -> #] & /@ ops;

matchQ[list_] :=


Module[{},

res = Fold[Replace[#1, List -> #2[[1]], {#2[[2]]}, Heads -> True] &,

list, Transpose@{{a, b, c}, {1, 2, 3}}] /. rules //.

Inactive[Subtract][x_, y_] :> Inactive[Plus][x, -y];

Select[res, Activate[#] == 24 &]]


list = {6, 4, 2, 3};

pattern = {{#[[1 ;; 2]], #[[3 ;; 4]]}, {#[[

1]], {#[[2]], #[[3 ;; 4]]}},

Reverse@{#[[1]], {#[[2]], #[[3 ;; 4]]}}, {{{#[[1]], #[[2]]}, #[[

3]]}, #[[4]]}, Reverse@{{{#[[1]], #[[2]]}, #[[3]]}, #[[4]]}} &;


parts = Flatten[(pattern) /@ Permutations[list, {4}], 1];

res1 = matchQ /@ parts // Quiet // Flatten;

When I'm playing with a calculating 24, I used some function like Inactive. My question is how can I make the output more reasonble in human writing habbit? For example, here I replace Subtract with Plus.


I want to change ((6+4)+-2)*3 to ((6+4)-2)*3


StringForm is also OK, just for display


res1[[1]]


(*
((6+4)+-2)*3
*)

enter image description here




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