diff options
Diffstat (limited to 'entries/jj/tm')
-rw-r--r-- | entries/jj/tm/fib-desc.txt | 66 | ||||
-rw-r--r-- | entries/jj/tm/fib.txt | 58 | ||||
-rw-r--r-- | entries/jj/tm/tm.nim | 192 |
3 files changed, 261 insertions, 55 deletions
diff --git a/entries/jj/tm/fib-desc.txt b/entries/jj/tm/fib-desc.txt index c766da6..289f927 100644 --- a/entries/jj/tm/fib-desc.txt +++ b/entries/jj/tm/fib-desc.txt @@ -11,14 +11,15 @@ A Turing machine is a 7-tuple T = (Q,Σ,Γ,δ,qI,qA,qR) where: - qR ∈ Q is the reject state - Q: { + ca, cb, cc, cd, ce, cf, cg, ch, ci, sa, sb, sc, sd, aa, ab, ac, aaa, aab, aac, aad, aae, aaf, - aba, abb, abc, abd, abe, abf, abg, abh, + aba, abb, abc, abd, abe, abf, ba, bb, bc, baa, bab, bac, bad, bae, baf, bba, bbb, bbc, bbd, bbe, bbf, - ca, cb, cc, cd, ce, cf, cg, ch, ci + za, zb, zc, zd } - Σ: not relevant as we entirely disregard the input to begin with. - Γ: {_, $, X, 0, 1, 0*, 1*} (_ means the blank symbol) @@ -43,7 +44,7 @@ states c*: clearing the initial tape δ(ca, Γ) -> (cb, $, R) δ(cb, Γ) -> (cc, 0, R) δ(cc, Γ) -> (cd, $, R) -δ(cd, Γ) -> (ce, 1, R) +δ(cd, Γ) -> (ce, 1*, R) δ(ce, Γ) -> (cf, $, R) δ(cf, Γ) -> (cg, 1, R) δ(cg, Γ) -> (ch, $, R) @@ -80,8 +81,8 @@ states a*: add the last digit of both numbers without carrying δ(aa, Γ \ $) -> (aa, , L) δ(aa, $) -> (ab, , L) +δ(ab, Γ \ {0,1,$}) -> (ab, , L) δ(ab, 0) -> (aaa, 0*, L) - δ(ab, 1) -> (aba, 1*, L) δ(ab, $) -> (ac, , R) @@ -100,13 +101,15 @@ states aa* δ(aac, Γ \ _) -> (aac, , R) δ(aac, _) -> (aad, , L) δ(aad, Γ \ X) -> (aad, , L) -δ(aad, X) -> (aba, 0, L) +δ(aad, X) -> (aa, 0, L) -δ(aab, 1*) -> (aad, 1, R) +δ(aab, 1*) -> (aae, 1, R) δ(aae, Γ \ _) -> (aae, , R) δ(aae, _) -> (aaf, , L) δ(aaf, Γ \ X) -> (aaf, , L) -δ(aaf, X) -> (baa, 1, L) +δ(aaf, X) -> (aa, 1, L) + +δ(aab, Γ \ {0*,1*,$}) -> (aab, , L) states ab* - read left until $, then read left until: @@ -123,35 +126,33 @@ states ab* δ(abd, Γ \ X) -> (abd, , L) δ(abd, X) -> (aa, 1, L) -δ(abb, $) -> (abe, , R) +δ(abb, 1*) -> (abe, 1, R) δ(abe, Γ \ _) -> (abe, , R) δ(abe, _) -> (abf, , L) δ(abf, Γ \ X) -> (abf, , L) -δ(abf, X) -> (aa, 1, L) +δ(abf, X) -> (ba, 0, L) -δ(abb, 1*) -> (abd, 1, R) -δ(abg, Γ \ _) -> (abg, , R) -δ(abg, _) -> (abh, , L) -δ(abh, Γ \ X) -> (abh, , L) -δ(abh, X) -> (ba, 0, L) +δ(abb, $) -> (abc, , R) + +δ(abb, Γ \ {0*,1*,$}) -> (abb, , L) states b*: add the last digit of both numbers while carrying a one - read left from end of tape, after reading $, until reading: - 0: replace with 0*, goto state (baa) - 1: replace with 1*, goto state (bba) - - $: do not replace, read right until _, goto state (ca) + - $: do not replace, read right until _, goto state (za) δ(ba, Γ \ $) -> (ba, , L) δ(ba, $) -> (bb, , L) +δ(bb, Γ \ {0,1,$}) -> (bb, , L) δ(bb, 0) -> (baa, 0*, L) - δ(bb, 1) -> (bba, 1*, L) δ(bb, $) -> (bc, , R) δ(bc, Γ \ _) -> (bc, , R) -δ(bc, _) -> (ca, , L) +δ(bc, _) -> (za, , L) states ba* - read left until $, then read left until: @@ -167,12 +168,14 @@ states ba* δ(bad, Γ \ X) -> (bad, , L) δ(bad, X) -> (aa, 1, L) -δ(bab, 1*) -> (bad, 1, R) +δ(bab, 1*) -> (bae, 1, R) δ(bae, Γ \ _) -> (bae, , R) δ(bae, _) -> (baf, , L) δ(baf, Γ \ X) -> (baf, , L) δ(baf, X) -> (ba, 0, L) +δ(bab, Γ \ {0*,1*,$}) -> (bab, , L) + states bb* - read left until $, then read left until: - 0*: replace with 0, read right until _, then read left until X and replace with 0, goto state (ba) @@ -187,27 +190,32 @@ states bb* δ(bbd, Γ \ X) -> (bbd, , L) δ(bbd, X) -> (ba, 0, L) -δ(bbb, 1*) -> (bbd, 1, R) +δ(bbb, 1*) -> (bbe, 1, R) δ(bbe, Γ \ _) -> (bbe, , R) δ(bbe, _) -> (bbf, , L) δ(bbf, Γ \ X) -> (bbf, , L) δ(bbf, X) -> (ba, 1, L) +δ(bbb, $) -> (bbc, , R) + +δ(bbb, Γ \ {0*,1*,$}) -> (bbb, , L) states c*: scooting over the computed number to make space for a carried digit - read left until $, then: - read right, noting the current number and writing the previous number - then go to state (sa) -δ(ca, Γ \ $) -> (ca, , L) -δ(ca, $) -> (cb, , L) +δ(za, Γ \ $) -> (za, , L) +δ(za, $) -> (zb, , R) + +δ(zb, Γ \ {0,1,_}) -> (zb, , R) +δ(zb, 0) -> (zc, 1, R) +δ(zb, 1) -> (zb, 1, R) +δ(zb, _) -> (zd, 1, R) -δ(cb, Γ \ {0,1,_}) -> (cb, , R) -δ(cb, 0) -> (cc, 1, R) -δ(cb, 1) -> (cb, 1, R) -δ(cb, _) -> (sa, 1, R) +δ(zc, Γ \ {0,1,_}) -> (zc, , R) +δ(zc, 0) -> (zc, 0, R) +δ(zc, 1) -> (zb, 0, R) +δ(zc, _) -> (zd, 0, R) -δ(cc, Γ \ {0,1,_}) -> (cc, , R) -δ(cc, 0) -> (cc, 0, R) -δ(cc, 1) -> (cb, 0, R) -δ(cc, _) -> (sa, 0, R) +δ(zd, _) -> (sa, $, R) diff --git a/entries/jj/tm/fib.txt b/entries/jj/tm/fib.txt index 43f4e55..3dd8bfc 100644 --- a/entries/jj/tm/fib.txt +++ b/entries/jj/tm/fib.txt @@ -11,14 +11,15 @@ A Turing machine is a 7-tuple T = (Q,Σ,Γ,δ,qI,qA,qR) where: - qR ∈ Q is the reject state - Q: { + ca, cb, cc, cd, ce, cf, cg, ch, ci, sa, sb, sc, sd, aa, ab, ac, aaa, aab, aac, aad, aae, aaf, - aba, abb, abc, abd, abe, abf, abg, abh, + aba, abb, abc, abd, abe, abf, ba, bb, bc, baa, bab, bac, bad, bae, baf, bba, bbb, bbc, bbd, bbe, bbf, - ca, cb, cc, cd, ce, cf, cg, ch, ci + za, zb, zc, zd } - Σ: not relevant as we entirely disregard the input to begin with. - Γ: {_, $, X, 0, 1, 0*, 1*} (_ means the blank symbol) @@ -33,7 +34,7 @@ A Turing machine is a 7-tuple T = (Q,Σ,Γ,δ,qI,qA,qR) where: δ(ca, Γ) -> (cb, $, R) δ(cb, Γ) -> (cc, 0, R) δ(cc, Γ) -> (cd, $, R) -δ(cd, Γ) -> (ce, 1, R) +δ(cd, Γ) -> (ce, 1*, R) δ(ce, Γ) -> (cf, $, R) δ(cf, Γ) -> (cg, 1, R) δ(cg, Γ) -> (ch, $, R) @@ -55,6 +56,7 @@ A Turing machine is a 7-tuple T = (Q,Σ,Γ,δ,qI,qA,qR) where: δ(aa, Γ \ $) -> (aa, , L) δ(aa, $) -> (ab, , L) +δ(ab, Γ \ {0,1,$}) -> (ab, , L) δ(ab, 0) -> (aaa, 0*, L) δ(ab, 1) -> (aba, 1*, L) δ(ab, $) -> (ac, , R) @@ -67,12 +69,13 @@ A Turing machine is a 7-tuple T = (Q,Σ,Γ,δ,qI,qA,qR) where: δ(aac, Γ \ _) -> (aac, , R) δ(aac, _) -> (aad, , L) δ(aad, Γ \ X) -> (aad, , L) -δ(aad, X) -> (aba, 0, L) -δ(aab, 1*) -> (aad, 1, R) +δ(aad, X) -> (aa, 0, L) +δ(aab, 1*) -> (aae, 1, R) δ(aae, Γ \ _) -> (aae, , R) δ(aae, _) -> (aaf, , L) δ(aaf, Γ \ X) -> (aaf, , L) -δ(aaf, X) -> (baa, 1, L) +δ(aaf, X) -> (aa, 1, L) +δ(aab, Γ \ {0*,1*,$}) -> (aab, , L) δ(aba, Γ \ $) -> (aba, , L) δ(aba, $) -> (abb, , L) @@ -81,24 +84,22 @@ A Turing machine is a 7-tuple T = (Q,Σ,Γ,δ,qI,qA,qR) where: δ(abc, _) -> (abd, , L) δ(abd, Γ \ X) -> (abd, , L) δ(abd, X) -> (aa, 1, L) -δ(abb, $) -> (abe, , R) +δ(abb, 1*) -> (abe, 1, R) δ(abe, Γ \ _) -> (abe, , R) δ(abe, _) -> (abf, , L) δ(abf, Γ \ X) -> (abf, , L) -δ(abf, X) -> (aa, 1, L) -δ(abb, 1*) -> (abd, 1, R) -δ(abg, Γ \ _) -> (abg, , R) -δ(abg, _) -> (abh, , L) -δ(abh, Γ \ X) -> (abh, , L) -δ(abh, X) -> (ba, 0, L) +δ(abf, X) -> (ba, 0, L) +δ(abb, $) -> (abc, , R) +δ(abb, Γ \ {0*,1*,$}) -> (abb, , L) δ(ba, Γ \ $) -> (ba, , L) δ(ba, $) -> (bb, , L) +δ(bb, Γ \ {0,1,$}) -> (bb, , L) δ(bb, 0) -> (baa, 0*, L) δ(bb, 1) -> (bba, 1*, L) δ(bb, $) -> (bc, , R) δ(bc, Γ \ _) -> (bc, , R) -δ(bc, _) -> (ca, , L) +δ(bc, _) -> (za, , L) δ(baa, Γ \ $) -> (baa, , L) δ(baa, $) -> (bab, , L) @@ -107,11 +108,12 @@ A Turing machine is a 7-tuple T = (Q,Σ,Γ,δ,qI,qA,qR) where: δ(bac, _) -> (bad, , L) δ(bad, Γ \ X) -> (bad, , L) δ(bad, X) -> (aa, 1, L) -δ(bab, 1*) -> (bad, 1, R) +δ(bab, 1*) -> (bae, 1, R) δ(bae, Γ \ _) -> (bae, , R) δ(bae, _) -> (baf, , L) δ(baf, Γ \ X) -> (baf, , L) δ(baf, X) -> (ba, 0, L) +δ(bab, Γ \ {0*,1*,$}) -> (bab, , L) δ(bba, Γ \ $) -> (bba, , L) δ(bba, $) -> (bbb, , L) @@ -120,21 +122,25 @@ A Turing machine is a 7-tuple T = (Q,Σ,Γ,δ,qI,qA,qR) where: δ(bbc, _) -> (bbd, , L) δ(bbd, Γ \ X) -> (bbd, , L) δ(bbd, X) -> (ba, 0, L) -δ(bbb, 1*) -> (bbd, 1, R) +δ(bbb, 1*) -> (bbe, 1, R) δ(bbe, Γ \ _) -> (bbe, , R) δ(bbe, _) -> (bbf, , L) δ(bbf, Γ \ X) -> (bbf, , L) δ(bbf, X) -> (ba, 1, L) +δ(bbb, $) -> (bbc, , R) +δ(bbb, Γ \ {0*,1*,$}) -> (bbb, , L) -δ(ca, Γ \ $) -> (ca, , L) -δ(ca, $) -> (cb, , L) +δ(za, Γ \ $) -> (za, , L) +δ(za, $) -> (zb, , R) -δ(cb, Γ \ {0,1,_}) -> (cb, , R) -δ(cb, 0) -> (cc, 1, R) -δ(cb, 1) -> (cb, 1, R) -δ(cb, _) -> (sa, 1, R) +δ(zb, Γ \ {0,1,_}) -> (zb, , R) +δ(zb, 0) -> (zc, 1, R) +δ(zb, 1) -> (zb, 1, R) +δ(zb, _) -> (zd, 1, R) -δ(cc, Γ \ {0,1,_}) -> (cc, , R) -δ(cc, 0) -> (cc, 0, R) -δ(cc, 1) -> (cb, 0, R) -δ(cc, _) -> (sa, 0, R) +δ(zc, Γ \ {0,1,_}) -> (zc, , R) +δ(zc, 0) -> (zc, 0, R) +δ(zc, 1) -> (zb, 0, R) +δ(zc, _) -> (zd, 0, R) + +δ(zd, _) -> (sa, $, R) diff --git a/entries/jj/tm/tm.nim b/entries/jj/tm/tm.nim new file mode 100644 index 0000000..42b9ff4 --- /dev/null +++ b/entries/jj/tm/tm.nim @@ -0,0 +1,192 @@ +# A simple Turing machine simulator implemented in Nim. + +import std/enumerate + +type Symbol = enum + `_`, `$`, `X`, `0`, `1`, `0*`, `1*`, + noop + +type Tape = seq[Symbol] + +type Direction = enum + L, R, S + +type State = enum + ca, cb, cc, cd, ce, cf, cg, ch, ci + sa, sb, sc, sd, + aa, ab, ac, + aaa, aab, aac, aad, aae, aaf, + aba, abb, abc, abd, abe, abf, + ba, bb, bc, + baa, bab, bac, bad, bae, baf, + bba, bbb, bbc, bbd, bbe, bbf, + za, zb, zc, zd + +type Transition = object + current_state: State + read_symbol: seq[Symbol] + next_state: State + write_symbol: Symbol + move_direction: Direction + +# convenience constructor +func δ(a: State, b: seq[Symbol], c: State, d: Symbol, e: Direction): Transition = + return Transition(current_state: a, read_symbol: b, next_state: c, write_symbol: d, move_direction: e) + +# safe get for an infinite tape: pretty, right? +func get(tape: var Tape, i: int): Symbol = + for j in tape.len .. i: + tape.add(`_`) + return tape[i] + +# safe set for an infinite tape +func set(tape: var Tape, i: int, s: Symbol) = + for j in tape.len .. i: + tape.add(`_`) + tape[i] = s + +let turing_machine = @[ + δ(ca, @[`_`, `$`, `X`, `0`, `1`, `0*`, `1*`], cb, `$`, R), + δ(cb, @[`_`, `$`, `X`, `0`, `1`, `0*`, `1*`], cc, `0`, R), + δ(cc, @[`_`, `$`, `X`, `0`, `1`, `0*`, `1*`], cd, `$`, R), + δ(cd, @[`_`, `$`, `X`, `0`, `1`, `0*`, `1*`], ce, `1*`, R), + δ(ce, @[`_`, `$`, `X`, `0`, `1`, `0*`, `1*`], cf, `$`, R), + δ(cf, @[`_`, `$`, `X`, `0`, `1`, `0*`, `1*`], cg, `1`, R), + δ(cg, @[`_`, `$`, `X`, `0`, `1`, `0*`, `1*`], ch, `$`, R), + δ(ch, @[`$`, `X`, `0`, `1`, `0*`, `1*`], ci, `_`, R), + δ(ch, @[`_`], sa, noop, S), + + δ(sa, @[`_`, `X`, `0`, `1`, `0*`, `1*`], sa, noop, L), + δ(sa, @[`$`], sb, noop, L), + δ(sb, @[`_`, `X`, `0*`, `1*`], sb, noop, L), + δ(sb, @[`0`], sc, `0*`, R), + δ(sb, @[`1`], sc, `1*`, R), + δ(sb, @[`$`], sd, noop, R), + δ(sc, @[`$`, `X`, `0`, `1`, `0*`, `1*`], sc, noop, R), + δ(sc, @[`_`], sa, `X`, L), + δ(sd, @[`$`, `X`, `0`, `1`], sd, noop, R), + δ(sd, @[`0*`], sd, `0`, R), + δ(sd, @[`1*`], sd, `1`, R), + δ(sd, @[`_`], aa, noop, L), + + δ(aa, @[`_`, `X`, `0`, `1`, `0*`, `1*`], aa, noop, L), + δ(aa, @[`$`], ab, noop, L), + δ(ab, @[`_`, `X`, `0*`, `1*`], ab, noop, L), + δ(ab, @[`0`], aaa, `0*`, L), + δ(ab, @[`1`], aba, `1*`, L), + δ(ab, @[`$`], ac, noop, R), + δ(ac, @[`$`, `X`, `0`, `1`, `0*`, `1*`], ac, noop, R), + δ(ac, @[`_`], sa, `$`, R), + + δ(aaa, @[`_`, `X`, `0`, `1`, `0*`, `1*`], aaa, noop, L), + δ(aaa, @[`$`], aab, noop, L), + δ(aab, @[`0*`], aac, `0`, R), + δ(aac, @[`$`, `X`, `0`, `1`, `0*`, `1*`], aac, noop, R), + δ(aac, @[`_`], aad, noop, L), + δ(aad, @[`_`, `$`, `0`, `1`, `0*`, `1*`], aad, noop, L), + δ(aad, @[`X`], aa, `0`, L), + δ(aab, @[`1*`], aae, `1`, R), + δ(aae, @[`$`, `X`, `0`, `1`, `0*`, `1*`], aae, noop, R), + δ(aae, @[`_`], aaf, noop, L), + δ(aaf, @[`_`, `$`, `0`, `1`, `0*`, `1*`], aaf, noop, L), + δ(aaf, @[`X`], aa, `1`, L), + δ(aab, @[`_`, `X`, `0`, `1`], aab, noop, L), + + δ(aba, @[`_`, `X`, `0`, `1`, `0*`, `1*`], aba, noop, L), + δ(aba, @[`$`], abb, noop, L), + δ(abb, @[`0*`], abc, `0`, R), + δ(abc, @[`$`, `X`, `0`, `1`, `0*`, `1*`], abc, noop, R), + δ(abc, @[`_`], abd, noop, L), + δ(abd, @[`_`, `$`, `0`, `1`, `0*`, `1*`], abd, noop, L), + δ(abd, @[`X`], aa, `1`, L), + δ(abb, @[`1*`], abe, `1`, R), + δ(abe, @[`$`, `X`, `0`, `1`, `0*`, `1*`], abe, noop, R), + δ(abe, @[`_`], abf, noop, L), + δ(abf, @[`_`, `$`, `0`, `1`, `0*`, `1*`], abf, noop, L), + δ(abf, @[`X`], ba, `0`, L), + δ(abb, @[`$`], abc, noop, R), + δ(abb, @[`_`, `X`, `0`, `1`], abb, noop, L), + + δ(ba, @[`_`, `X`, `0`, `1`, `0*`, `1*`], ba, noop, L), + δ(ba, @[`$`], bb, noop, L), + δ(bb, @[`_`, `X`, `0*`, `1*`], bb, noop, L), + δ(bb, @[`0`], baa, `0*`, L), + δ(bb, @[`1`], bba, `1*`, L), + δ(bb, @[`$`], bc, noop, R), + δ(bc, @[`$`, `X`, `0`, `1`, `0*`, `1*`], bc, noop, R), + δ(bc, @[`_`], za, noop, L), + + δ(baa, @[`_`, `X`, `0`, `1`, `0*`, `1*`], baa, noop, L), + δ(baa, @[`$`], bab, noop, L), + δ(bab, @[`0*`], bac, `0`, R), + δ(bac, @[`$`, `X`, `0`, `1`, `0*`, `1*`], bac, noop, R), + δ(bac, @[`_`], bad, noop, L), + δ(bad, @[`_`, `$`, `0`, `1`, `0*`, `1*`], bad, noop, L), + δ(bad, @[`X`], aa, `1`, L), + δ(bab, @[`1*`], bae, `1`, R), + δ(bae, @[`$`, `X`, `0`, `1`, `0*`, `1*`], bae, noop, R), + δ(bae, @[`_`], baf, noop, L), + δ(baf, @[`_`, `$`, `0`, `1`, `0*`, `1*`], baf, noop, L), + δ(baf, @[`X`], ba, `0`, L), + δ(bab, @[`_`, `X`, `0`, `1`], bab, noop, L), + + δ(bba, @[`_`, `X`, `0`, `1`, `0*`, `1*`], bba, noop, L), + δ(bba, @[`$`], bbb, noop, L), + δ(bbb, @[`0*`], bbc, `0`, R), + δ(bbc, @[`$`, `X`, `0`, `1`, `0*`, `1*`], bbc, noop, R), + δ(bbc, @[`_`], bbd, noop, L), + δ(bbd, @[`_`, `$`, `0`, `1`, `0*`, `1*`], bbd, noop, L), + δ(bbd, @[`X`], ba, `0`, L), + δ(bbb, @[`1*`], bbe, `1`, R), + δ(bbe, @[`$`, `X`, `0`, `1`, `0*`, `1*`], bbe, noop, R), + δ(bbe, @[`_`], bbf, noop, L), + δ(bbf, @[`_`, `$`, `0`, `1`, `0*`, `1*`], bbf, noop, L), + δ(bbf, @[`X`], ba, `1`, L), + δ(bbb, @[`_`, `X`, `0`, `1`], bbb, noop, L), + δ(bbb, @[`$`], bbc, noop, R), + + δ(za, @[`_`, `X`, `0`, `1`, `0*`, `1*`], za, noop, L), + δ(za, @[`$`], zb, noop, R), + + δ(zb, @[`$`, `X`, `0*`, `1*`], zb, noop, R), + δ(zb, @[`0`], zc, `1`, R), + δ(zb, @[`1`], zb, `1`, R), + δ(zb, @[`_`], zd, `1`, R), + + δ(zc, @[`$`, `X`, `0*`, `1*`], zc, noop, R), + δ(zc, @[`0`], zc, `0`, R), + δ(zc, @[`1`], zb, `0`, R), + δ(zc, @[`_`], zd, `0`, R), + + δ(zd, @[`_`], sa, `$`, R) +] + +proc print(state: State, tape: Tape, position: int) = + stdout.write($state) + for i, s in enumerate(tape): + if i == position: + stdout.write("[" & $s & "]") + elif s == `$`: + stdout.write(" ") + else: + stdout.write($s) + stdout.write("\n") + +var state = ca +var position = 0 +var tape = @[`_`] + +proc step() = + # print(state, tape, position) + for δ in turing_machine: + if state == δ.current_state and tape.get(position) in δ.read_symbol: + state = δ.next_state + if δ.write_symbol != noop: tape.set(position, δ.write_symbol) + if δ.move_direction == L: position.dec + elif δ.move_direction == R: position.inc + return + echo "Invalid state! crashing" + quit() + +while true: + step() |