Rare numbers: Difference between revisions

It could look something like the following (ignoring whatever optimizations the other examples are using), if it was fast enough. I did not have the time/processor to test finding the first 5. The .israre() function appears to return the right answer, tested with individual numbers.

<syntaxhighlight lang="langur">val .perfectsquare = fn(.n) { (.n ^/ 2) div 1 }

val .israre = fn(.n) {

val .r = reverse(.n)

if .n == .r: return false

val .sum = .n + .r

val .diff = .n - .r

.diff > 0 and .perfectsquare(.sum) and .perfectsquare(.diff)

val .findfirst = fn(.maxmx) {

for[=[]] .i = 0; len(_for) < .maxmx; .i += 1 {

if .israre(.i) {

_for ~= [.i]

writeln "the first 5 rare numbers: ", .findfirst(5)</syntaxhighlight>