Shortest Path

public static int countTurns(int A, int B){
 
        //check a and b. If either a or b is at 0, we know we're stuck.
        if(A == 0 && B == 0)
            return 0;
        else if(A == 0 || B == 0)
            return -1;
 
        //declare some variables.
        int turns = 0;
 
        //now convert them to their positive form.
        int a = Math.abs(A);
        int b = Math.abs(B);
 
        //now make our loop.
        while(a != 0 && b != 0){
 
            //check who to move first.
            if(a > b){
                //move a 2 and b 1.
                a -=2;
                b -=1;
            } else {
                a -=1;
                b -=2;
            }
 
            //now add our turn.
            turns += 1;
 
            //check for our 100,000,000
            if(turns > 100000000)
                return -2;
 
        }
 
        //now a bit more logic.
        if(a == 0 && b == 0)
            return turns;
        else
            return -1;
 
        // thats it!
    }