Merge pull request 'On branch first' (#8) from first into master

Reviewed-on: #8

script_GCD.sh

@@ -0,0 +1,13 @@
+#!/bin/bash
+
+a=$1
+b=$2
+
+while [ $b -ne 0 ]
+do
+    temp=$b
+    b=$((a % b))
+    a=$temp
+done
+
+echo $a