Self-describing numbers

LRCVS 08.05.11

Self-describing numbers:

There are several integers numbers called "self-describing".

Integers with the property that, when digit positions are labeled 0 to N-1, the digit in each position is equal to the number of times that that digit appears in the number.

For example 2020 is a four digit self describing number.

Position "0" has value 2 and there is two 0 in the number. Position "1" has value 0 because there are not 1's in the number. Position "2" has value 2 and there is two 2. And the position "3" has value 0 and there are zero 3's.

Self-describing numbers < 100.000.000 : 1210 - 2020 - 21200 - 3211000 - 42101000

.......................................... The following example is written in Basic ..........................................

lang "qb"

Dim x, r, b, c, n, m As Integer

Dim a, d As String

Dim v(10), w(10) As Integer

Cls

For x = 1 To 5000000

a$ = ltrim$(Str$(x))

b = Len(a$)

For c = 1 To b

d$ = Mid$(a$, c, 1)

v(Val(d$)) = v(Val(d$)) + 1

w(c - 1) = Val(d$)

Next c

r = 0

For n = 0 To 10

If v(n) = w(n) Then r = r + 1

v(n) = 0

w(n) = 0

Next n

If r = 11 Then Print x; " Yes,is autodescriptive number"

Next x

Print

Print "End"

sleep

end

.........................................................................

This example is written in another language Logo (FMSLogo)

........................................................................

TO XX

BT

MAKE "AA (ARRAY 10 0) MAKE "BB (ARRAY 10 0)

FOR [Z 0 9][SETITEM :Z :AA "0 SETITEM :Z :BB "0 ]

FOR [A 1 50000][

MAKE "B COUNT :A

MAKE "Y 0

MAKE "X 0

MAKE "R 0

MAKE "J 0

MAKE "K 0

FOR [C 1 :B][MAKE "D ITEM :C :A

SETITEM :C - 1 :AA :D

MAKE "X ITEM :D :BB

MAKE "Y :X + 1

SETITEM :D :BB :Y

MAKE "R 0]

FOR [Z 0 9][MAKE "J ITEM :Z :AA

MAKE "K ITEM :Z :BB

IF :J = :K [MAKE "R :R + 1]]

IF :R = 10 [PR :A]

FOR [Z 0 9][SETITEM :Z :AA "0 SETITEM :Z :BB "0 ]]

PR [END]

END