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 static void main(String[] args) {
        String thisIsASample = new Solution().trans(
            "This is a sample", 16);
        System.out.println(thisIsASample);
    }
    public String trans (String s, int n) {
        char[] arrary = s.toCharArray();
        for (int i = 0, j = s.length() - 1; i <= j; i++, j--) {
            //反转开始
    
            if (arrary[i] == ' ') {

            } else if (arrary[i] >= 'a' && arrary[i] <= 'z') {
                arrary[i] = (char)(arrary[i] - 32);
            } else {
                arrary[i] = (char)(arrary[i] + 32);
            }
            //反转结尾
            if(i!=j)
            if (arrary[j] == ' ') {

            } else if (arrary[j] >= 'a' && arrary[j] <= 'z') {
                arrary[j] = (char)(arrary[j] - 32);
            } else {
                arrary[j] = (char)(arrary[j] + 32);
            }
            //交换
            char tem = arrary[j];
            arrary[j] = arrary[i];
            arrary[i] = tem;
        }

       // System.out.println(new String(arrary));

        //反转单词
        for (int i = 0; i < s.length();) {
            if (arrary[i] == ' ') {
                i++;
                continue;
            }
            int start = i, end = i;
            for (int j = i + 1; j < n && arrary[j] != ' '; j++) {
                end = j;
                if (j == s.length()) {
                    break;
                }
            }
            i = end + 1;
            
            while (start <= end) {
                char tem = arrary[start];
                arrary[start] = arrary[end];
                arrary[end] = tem;
                start++;
                end--;
            }
        }

        return new String(arrary);
    }
}