docs: protected static float costReplace(char x, char y) {
  		int cost = 1;
  		for(char[] xy: repCostChars){
  			if(xy[0]==x&&xy[1]==y){
  				cost =2;
  				break;
  			}else if(xy[0]==y&&xy[1]==x){
  				cost =2;
  				break;
  			}
  		}
  		return cost;//noCostChars.indexOf(c)!=-1?1:0;
  	}