Change custom url to base url in godaddy shared hosing

I want to redirect www.xyz.com to www.xyz.com/public or If I type www.xyz.com in my addres bar, i want to see contents in www.xyz.com/public. How will I do this in my shared godaddy hosting. In localhost I did this by editing my virtual host. How will I edit my virtual host in shared webhosting in godaddy??

can anyone help??