[프로그래머스] 다항식 더하기

class Solution {
    public String solution(String polynomial) {
        int xCount = 0; int numCount = 0;

        for (String s : polynomial.split(" ")) {
            if (s.contains("x")) {
                xCount += s.equals("x") ? 1 : Integer.parseInt(s.replaceAll("x", ""));
            } else if (!s.equals("+")) {
                numCount += Integer.parseInt(s);
            }
        }
        
        return (xCount != 0 ? (xCount > 1 ? xCount + "x" : "x") : "") 
        		+ (numCount != 0 ? (xCount != 0 ? " + " : "") 
                + numCount : xCount == 0 ? "0" : "");
    }
}