IDFC Bank Ltd Shares

I have 5000 shares of IDFC Ltd. After the demerger with IDFC Bank Ltd, I have get 5000 Shares of IDFC Bank Ltd. After 10 days I have sold both the Shares of IDFC and IDFC bank Ltd. Now what would be the cost of acquisition of IDFC Bank shares?

In this case the cost of acquisition of IDFC Bank would be zero for accounting and tax related purposes. But as we all know there is no such thing as free money the gain is IDFC Bank is compensated by the capital loss in IDFC ltd So,net gain or loss would be zero.

Siva I want to know how will i show the shares of IDFC Bank as it has been provided by scheme of arrangement.