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Initial data commit

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Ingy döt Net 2023-07-01 11:58:00 -04:00
parent 72d218235f
commit f23f22d71c
199087 changed files with 3378941 additions and 0 deletions
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43
Task/Matrix-chain-multiplication/Mathematica/matrix-chain-multiplication.math Normal file
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ClearAll[optim, aux]
optim[a_List] := Module[{u, v, n, c, r, s},
n = Length[a] - 1;
u = ConstantArray[0, {n, n}];
v = ConstantArray[\[Infinity], {n, n}];
u[[All, 1]] = -1;
v[[All, 1]] = 0;
Do[
Do[
Do[
c =
v[[i, k]] + v[[i + k, j - k]] + a[[i]] a[[i + k]] a[[i + j]];
If[c < v[[i, j]],
u[[i, j]] = k;
v[[i, j]] = c;
]
,
{k, 1, j - 1}
]
,
{i, 1, n - j + 1}
]
,
{j, 2, n}
];
r = v[[1, n]];
s = aux[u, 1, n];
{r, s}
]
aux[u_, i_, j_] := Module[{k},
k = u[[i, j]];
If[k < 0,
i
,
Inactive[Times][aux[u, i, k], aux[u, i + k, j - k]]
]
]
{r, s} = optim[{1, 5, 25, 30, 100, 70, 2, 1, 100, 250, 1, 1000, 2}];
r
s
{r, s} = optim[{1000, 1, 500, 12, 1, 700, 2500, 3, 2, 5, 14, 10}];
r
s