Building

function building(input){
	var numFloors = Number(input.shift());
  	var numRoomsOnOneFloor = Number(input.shift());
	var arrFloors = [];
	var floor = "";

  	for(var i = numFloors; i > 0; i--){
    	for(var j = 0; j < numRoomsOnOneFloor; j++){
            if(i == numFloors){
			  floor += ` L${i}${j}`;
        	}
          	else{
              if(i%2 == 0)
              {
                  //cheten etaj
				  floor += ` O${i}${j}`;
              }
              else floor += ` A${i}${j}`;
            }
        }
		arrFloors[numFloors-i]=floor;
		floor = "";
    }

	for(var i = 0; i < arrFloors.length; i++)
		console.log(arrFloors[i]);
}