比较含退格的字符串

/*
 * 题目思路：
 * 利用Java Stream简化对字符串中退格字符 '#' 的处理。使用reduce方法模拟栈的操作。
 */

import java.util.stream.Collectors;
import java.util.stream.IntStream;

public class Solution {
    public boolean backspaceCompare(String s, String t) {
        return processString(s).equals(processString(t));
    }

    private String processString(String str) {
        return IntStream.range(0, str.length())
                .mapToObj(i -> str.charAt(i))
                .collect(Collectors.toList())
                .stream()
                .reduce(new StringBuilder(), (sb, ch) -> {
                    if (ch != '#') {
                        sb.append(ch);
                    } else if (sb.length() > 0) {
                        sb.deleteCharAt(sb.length() - 1);
                    }
                    return sb;
                }, (sb1, sb2) -> sb1.append(sb2)).toString();
    }

    public static void main(String[] args) {
        Solution solution = new Solution();
        System.out.println(solution.backspaceCompare("ab#c", "ad#c")); // 输出: true
        System.out.println(solution.backspaceCompare("ab##", "c#d#")); // 输出: true
        System.out.println(solution.backspaceCompare("a#c", "b"));    // 输出: false
    }
}