Mathematica 24点程序！

cjilyy

f[x1_, s1_, x2_, s2_, x3_, s3_, x4_] :=
8 G2 T# J; X6 v; W: ] Module[{result, i},
  result = {HoldForm[(x1~s1~x2)~s2~(x3~s3~x4)],
1 s5 B) h- |! l  |- F0 H1 D$ p    HoldForm[x1~s1~(x2~s2~x3~s3~x4)],
4 i# U6 K5 ?  I9 E5 p+ A7 r# P    HoldForm[x1~s1~x2~s2~(x3~s3~x4)],
    HoldForm[(x1~s1~x2~s2~x3)~s3~x4],
    HoldForm[x1~s1~(x2~s2~x3)~s3~x4],
4 X+ f$ Q( W/ \5 [) s    HoldForm[(x1~s1~(x2~s2~x3))~s3~x4],
    HoldForm[x1~s1~(x2~s2~(x3~s3~x4))]};
  result = Union[result];
  For[i = 1, i <= Length[result], i++,
   If[ReleaseHold[result[[i]]] == 24, Print[result[[i]], "=24"];
     (*Print[TreeForm[result[[i]],DirectedEdges->True]]*);];];]
0 w5 h, ~( m: ~
fs[x1_, x2_, x3_, x4_] :=
Module[{result, s, sym, num, i, j}, Off[Divide::infy];
  Off[Part::partw];
$ V" I/ D4 {% q2 @* l5 ~  Off[Divide::indet];
* i, s) B- M3 c" ~' {  s = {Plus, Subtract, Times, Divide};
  sym = Flatten[
* V  H6 d5 N5 [7 B% ]% ~    Table[{s[[i]], s[[j]], s[[k]]}, {i, 4}, {j, 4}, {k, 4}], 2];
, G9 i9 b; Q- V; w0 \0 C  sym = Union[sym];
  num = Permutations[{x1, x2, x3, x4}];
" ]* L& b: V# e; v5 u5 N  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,
& I: \$ p0 \, u- t, E    Length[sym]}]]
2 c% I& k5 i4 S9 f
- P8 `% @; _+ |' c7 r1 k( jfs[3, 3, 8, 8]