SRM 528 DIV 2 250 problem

My Answer is 

public class BishopMove {

public static void main(String[] args){

System.out.println(howManyMoves(4, 6, 7, 3));

System.out.println(howManyMoves(2, 5, 2, 5));

System.out.println(howManyMoves(1, 3, 5, 5));

System.out.println(howManyMoves(4, 6, 7, 4));

}

public static int howManyMoves(int r1, int c1, int r2, int c2){

if((r1 + c1) %2 != (r2 + c2)%2){

return -1;

}

if(r1 == r2 && c1==c2){

return 0;

}

if(Math.abs(r1-r2) == Math.abs(c1-c2)){

return 1;

}else{

return 2;

}

}

}