diff --git a/tools/diffoptimized.sh b/tools/diffoptimized.sh
index 42286c7..5264cbb 100755
--- a/tools/diffoptimized.sh
+++ b/tools/diffoptimized.sh
@@ -1,13 +1,14 @@
 #!/bin/bash
 
-CBC=../bin/cbc
+CBC=$(dirname $0)/../bin/cbc
 
 for src in "$@"
 do
     if $CBC $src >/dev/null 2>&1
     then
+        asm=$(basename $src .cb).s
         echo "$src:"
-        $CBC -O -S $src -o ${src%%.cb}.s.opt &&
-        diff -u ${src%%.cb}.s ${src%%.cb}.s.opt
+        $CBC -O -S $src -o $asm.opt &&
+        diff -u $asm $asm.opt
     fi
 done