Mathematica 24点程序！

cjilyy

f[x1_, s1_, x2_, s2_, x3_, s3_, x4_] :=
Module[{result, i},
  result = {HoldForm[(x1~s1~x2)~s2~(x3~s3~x4)],
    HoldForm[x1~s1~(x2~s2~x3~s3~x4)],
7 X' b3 G( X/ I% s* \" o% L1 n  {* F    HoldForm[x1~s1~x2~s2~(x3~s3~x4)],
    HoldForm[(x1~s1~x2~s2~x3)~s3~x4],
    HoldForm[x1~s1~(x2~s2~x3)~s3~x4],
    HoldForm[(x1~s1~(x2~s2~x3))~s3~x4],
# ~& x# t1 p# ]- {    HoldForm[x1~s1~(x2~s2~(x3~s3~x4))]};
  result = Union[result];
  For[i = 1, i <= Length[result], i++,
& R, O# U6 h9 ^   If[ReleaseHold[result[[i]]] == 24, Print[result[[i]], "=24"];
- |" _0 }, H) X- C. x+ N* q$ f     (*Print[TreeForm[result[[i]],DirectedEdges->True]]*);];];]
; M( F0 J, @, C
& ~  w: P0 [3 l  ]7 Y1 h7 Mfs[x1_, x2_, x3_, x4_] :=
9 }5 Z( }- l; Y3 n3 X Module[{result, s, sym, num, i, j}, Off[Divide::infy];
# u2 p- k  I% v7 p# R9 s1 {  Off[Part::partw];
  Off[Divide::indet];
% k( M6 ]: `" T; Q- f+ n  s = {Plus, Subtract, Times, Divide};
4 @- Y  P) D+ W5 h4 l  sym = Flatten[
    Table[{s[[i]], s[[j]], s[[k]]}, {i, 4}, {j, 4}, {k, 4}], 2];
6 L/ n2 A  q; H6 Z9 E8 ~/ q$ s  sym = Union[sym];
  num = Permutations[{x1, x2, x3, x4}];
5 m. I9 O- R  a5 X1 W  Do[f[num[[i, 1]], sym[[j, 1]], num[[i, 2]], sym[[j, 2]],
    num[[i, 3]], sym[[j, 3]], num[[i, 4]]], {i, Length[num]}, {j,
; e, d6 a: ?( s- Z0 E+ N9 h    Length[sym]}]]
/ X  n( F: y3 w; H1 ~1 \
3 q# d2 z# c' W' `7 O! u% }, cfs[3, 3, 8, 8]