1 files changed, 41 insertions, 0 deletions
diff --git a/gcd.bas b/gcd.bas
new file mode 100644
index 0000000..f63fd23
--- /dev/null
+++ b/gcd.bas
@@ -0,0 +1,41 @@
+' Tested with FreeBASIC 1.10.0
+'
+' Synopsis:
+' $ fbc -x gcd-bas gcd.bas
+' $ ./gcd-bas 11 22 33 121
+'
+
+FUNCTION gcd2 (BYVAL a AS ULONGINT, BYVAL b AS ULONGINT) AS ULONGINT
+  DIM c AS ULONGINT
+  DO WHILE (b > 0)
+    c = b
+    b = a MOD b
+    a = c
+  LOOP
+  RETURN a
+END FUNCTION
+
+
+FUNCTION gcdn (nums() AS ULONGINT) AS ULONGINT
+  DIM gcd AS ULONGINT = nums(LBOUND(nums))
+  FOR i AS INTEGER = LBOUND(nums) + 1 TO UBOUND(nums)
+    gcd = gcd2(gcd, nums(i))
+  NEXT
+  RETURN gcd
+END FUNCTION
+
+
+DIM argc AS INTEGER = 0
+DO WHILE (LEN(COMMAND(argc + 1)) > 0)
+  argc += 1
+LOOP
+
+IF argc = 0 THEN STOP
+
+DIM nums(argc) AS ULONGINT
+FOR i AS INTEGER = 1 TO argc
+  nums(i) = VALULNG(COMMAND(i))
+NEXT
+
+PRINT gcdn(nums())
+