Data commit

Task/Smith-numbers/Sidef/smith-numbers.sidef

@@ -0,0 +1,36 @@
+var primes = Enumerator({ |callback|
+    static primes = Hash()
+    var p = 2
+    loop {
+        callback(p)
+        p = (primes{p} := p.next_prime)
+    }
+})
+
+func factors(remainder) {
+
+    remainder == 1 && return([remainder])
+
+    gather {
+        primes.each { |factor|
+            if (factor*factor > remainder) {
+                take(remainder) if (remainder > 1)
+                break
+            }
+
+            while (factor.divides(remainder)) {
+                take(factor)
+                break if ((remainder /= factor) == 1)
+            }
+        }
+    }
+}
+
+func is_smith_number(n) {
+    !n.is_prime && (n.digits.sum == factors(n).join.to_i.digits.sum)
+}
+
+var s = range(2, 10_000).grep { is_smith_number(_) }
+say "#{s.len} Smith numbers below 10_000"
+say "First 10: #{s.first(10)}"
+say "Last  10: #{s.last(10)}"