Self numbers: Difference between revisions

=={{header|jq}}==

'''Adapted from [[#Julia|Julia]]'''

{{works with|jq}}

<lang jq>

def sumdigits: tostring | explode | map([.]|implode|tonumber) | add;

def gsum: . + sumdigits;

def isnonself:

def ndigits: tostring|length;

. as $i

| ($i - ($i|ndigits)*9) as $n

| any( range($i-1; [0,$n]|max; -1);

gsum == $i);

# an array

def last81:

[limit(81; range(1; infinite) | select(isnonself))];

# output an unbounded stream

def selfnumbers:

foreach range(1; infinite) as $i ( [0, last81];

.[0] = false

| .[1] as $last81

| if $last81 | bsearch($i) < 0

then .[0] = $i

| if $i > $last81[-1] then .[1] = $last81[1:] + [$i | gsum ] else . end

else .

end;

.[0] | select(.) );

"The first 50 self numbers are:", last81[:50],

"",

(nth(100000000 - 1; selfnumbers)

| if . == 1022727208

then "Yes, \(.) is the 100,000,000th self number."

else "No, \(.i) is actually the 100,000,000th self number."

end)</lang>

{{out}}

<pre>

The first 50 self numbers are:

[2,4,6,8,10,11,12,13,14,15,16,17,18,19,21,22,23,24,25,26,27,28,29,30,32,33,34,35,36,37,38,39,40,41,43,44,45,46,47,48,49,50,51,52,54,55,56,57,58,59]

Yes, 1022727208 is the 100,000,000th self number.

</pre>