一、题目内容

二、题解

解法1：

思路

Character.isUpperCase(c)

代码

public class Solution {
    public String trans(String s, int n) {
        // write code here
        String[] arr = s.split(" ",-1);
        StringBuilder ans = new StringBuilder();
        for(int i = arr.length-1;i>=0;i--){
            ans.append(reverse(arr[i]));
            if(i == 0){
                break;
            }
            ans.append(" ");
        }
        return ans.toString();
    }
    private String reverse(String str){
        StringBuilder sb = new StringBuilder();
        for(char c: str.toCharArray()){
            if(Character.isUpperCase(c)){
                sb.append(Character.toLowerCase(c));
            }else{
                sb.append(Character.toUpperCase(c));
            }
        }
        return sb.toString();
    }
}