A type (cont) followed by a variable name (c) is the syntax for declaring a variable. So when you say "cont c" a
second time,
Java thinks you're trying to declare a
second variable with the same name as the first.
If you want to use the same c after declaring it, just use the variable name
without the type...
cont c = new cont(); //declaration (and assignment)
c = new cont(6); //reassignment
If you want a
different variable, then provide the type for the new variable...
cont c = new cont();
cont d = new cont(6);