Truncatable primes: Difference between revisions

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 is the largest right truncatable prime <= 1000000.
 </lang>
+=={{header|Nimrod}}==
+{{trans|Python}}
+<lang nimrod>import sets, strutils, algorithm
+proc primes(n): seq[int] =
+  result = @[]
+  var multiples = initSet[int]()
+  for i in 2..n:
+    if i notin multiples:
+      result.add i
+      for j in countup(i*i, n, i):
+        multiples.incl j
+proc truncatablePrime(n): tuple[left: int, right: int] =
+  var
+    primelist: seq[string] = @[]
+  for x in primes(n):
+    primelist.add($x)
+  reverse primelist
+  var primeset = toSet primelist
+  for n in primelist:
+    var alltruncs = initSet[string]()
+    for i in 0..n.len:
+      alltruncs.incl n[1..n.high]
+    if alltruncs <= primeset:
+      result.left = parseInt(n)
+      break
+  for n in primelist:
+    var alltruncs = initSet[string]()
+    for i in 0..n.len:
+      alltruncs.incl n[0..i]
+    if alltruncs <= primeset:
+      result.right = parseInt(n)
+      break
+echo truncatablePrime(1000000)</lang>
+Output:
+<pre>(left: 999961, right: 739399)</pre>
 =={{header|ooRexx}}==
 <lang ooRexx>