题解 | 点击消除

import java.util.Iterator;
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner reader = new Scanner(System.in);

		char[] chs = reader.nextLine().toCharArray();
		char[] temp = new char[chs.length];
		int i = 0;
		for (int j = 0; j < chs.length; j++) {
			if (i == 0) {
				temp[i] = chs[j];
				i++;
			} else {
				if (temp[i - 1] == chs[j]) {
					i--;
				} else {
					temp[i] = chs[j];
					i++;
				}
			}
		}
		StringBuilder result = new StringBuilder();
		for (int j = 0; j < i; j++) {
			result.append(temp[j]);
		}

		System.out.println(i == 0 ? 0 : result.toString());

		reader.close();
	}

}