I did a logic network with only NAND gates to function below: 

[![enter image description here](https://i.stack.imgur.com/6fmOT.png)](https://i.stack.imgur.com/6fmOT.png)

and my logic newtork

[![enter image description here](https://i.stack.imgur.com/0T79D.png)](https://i.stack.imgur.com/0T79D.png)

Is it correct?