Initial data commit

Task/Greatest-common-divisor/MySQL/greatest-common-divisor.sql

@@ -0,0 +1,24 @@
+DROP FUNCTION IF EXISTS gcd;
+DELIMITER |
+
+CREATE FUNCTION gcd(x INT, y INT)
+RETURNS INT
+BEGIN
+  SET @dividend=GREATEST(ABS(x),ABS(y));
+  SET @divisor=LEAST(ABS(x),ABS(y));
+  IF @divisor=0 THEN
+    RETURN @dividend;
+  END IF;
+  SET @gcd=NULL;
+  SELECT gcd INTO @gcd FROM
+    (SELECT @tmp:=@dividend,
+            @dividend:=@divisor AS gcd,
+            @divisor:=@tmp % @divisor AS remainder
+       FROM mysql.help_relation WHERE @divisor>0) AS x
+    WHERE remainder=0;
+  RETURN @gcd;
+END;|
+
+DELIMITER ;
+
+SELECT gcd(12345, 9876);