Data commit

Task/Duffinian-numbers/FreeBASIC/duffinian-numbers.basic

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+#include "isprime.bas"
+
+Function GCD(p As Integer, q As Integer) As Integer
+    Return Iif(q = 0, p, GCD(q, p Mod q))
+End Function
+
+Function SumDiv(Num As Uinteger) As Uinteger
+    Dim As Uinteger Div = 2, Sum = 0, Quot
+    Do
+        Quot = Num / Div
+        If Div > Quot Then Exit Do
+        If Num Mod Div = 0 Then
+            Sum += Div
+            If Div <> Quot Then Sum += Quot
+        End If
+        Div += 1
+    Loop
+    Return Sum+1
+End Function
+
+Function Duff(N As Uinteger) As Boolean
+    Return Iif(isPrime(N), False, GCD(SumDiv(N), N) = 1)
+End Function
+
+Dim As Integer C = 0, N = 4
+Print "First 50 Duffinian numbers:"
+Do
+    If Duff(N) Then
+        Print Using "####"; N;
+        C += 1
+        If C Mod 20 = 0 Then Print
+    End If
+    N += 1
+Loop Until C >= 50
+
+C = 0 : N = 4
+Print !"\n\nFirst 50 Duffinian triplets:"
+Do
+    If Duff(N) And Duff(N+1) And Duff(N+2) Then
+        Print Using !" [###### ###### ######]\t"; N; N+1; N+2;
+        C += 1
+        If C Mod 4 = 0 Then Print
+    End If
+    N += 1
+Loop Until C >= 50
+
+Sleep