Question

How to control to which if the else is correlated?

ex:

if X = 1 { // A
   if Y > 1 { // B
      gothere();
   }
}
else if X < 1 { // C
    gohere();
}
else { // D
   gonowhere();
}

how to make sure C and D will not be related to B???

here´s another example:

if xxx {

    ...

FM_log(7,"vList.length = "+vList.length);

if (skippingAvancado) 
   if (vList.length > 1)        
    changeVillage();
else {
   if (skipcounter >= maxSkipCount) {
       FM_log(7,"ROTINA ANTIGA SKIPCOUNTER");
       changeVillage();
   }
}
else {

Answer 1

This is the dangling else problem; it’s ambiguous and the language can choose either construct to bind to. Most (if not all) languages group the else with the nearest if, so it would be

if(foo)
    if(bar)
       baz;
    else
       bazz;

In practice you should always use braces to make sure there’s no ambiguity, as you did in your first example. If you took the braces out of the first example, C and D would be attached to B instead of A; since you included them, the blocks work as you wanted