The curly braces are just grouping symbols. The state assignments and corresponding break statements must be kept together. In the case of the if statement in state 6 it would normally be formatted as one statement without curly braces at all. Like this:
case 6:
if (v1<k2)
{
state=5;
break;
}
state=0;
break;
default:
state=1;
break;