题解 | #字符串变形#

import java.util.*;


public class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     *
     * @param s string字符串
     * @param n int整型
     * @return string字符串
     */
    public String trans(String s, int n) {
        // write code here
        if (s == "\""){
            return s;
        }
        StringBuilder sb = new StringBuilder();
        StringBuilder res = new StringBuilder();
        String[] split = s.split(" ", -1);
        for (int i = split.length - 1; i >= 0; i--) {
            sb.append(split[i]).append(" ");
        }
        sb.deleteCharAt(sb.length() - 1);
        for (int i = 0; i < sb.length(); i++) {
            char c = sb.charAt(i);
            if (Character.isLowerCase(sb.charAt(i))) {
                c = Character.toUpperCase(c);
            } else if (Character.isUpperCase(sb.charAt(i))) {
                c = Character.toLowerCase(c);
            }
            res.append(c);
        }
        
        return res.toString();
    }
}