题解 | 小苯的IDE括号问题（easy）

import java.util.*;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        // 注意 hasNext 和 hasNextLine 的区别
        Scanner in = new Scanner(System.in);
        int stringLength = in.nextInt();
        int inputLine = in.nextInt();
        String inputStream = in.next();
        char[] charArray = new char[stringLength];
        int iNodeIndex = -1;

        for (int i = 0; i < stringLength; i ++) {
            char value = inputStream.charAt(i);
            charArray[i] = value;
            if (value == 'I') {
                iNodeIndex = i;
            }
        }

        int preIndex = iNodeIndex - 1;
        int nextIndex = iNodeIndex + 1;

        for (int i = 0; i < inputLine; i++) {
            String string = in.next();
            if (string.equalsIgnoreCase("backspace")) {
                if (preIndex == -1) {
                    continue;
                }

                char value = charArray[preIndex];
                if (value == '(' && nextIndex < stringLength && charArray[nextIndex] == ')') {
                    preIndex--;
                    nextIndex++;
                } else {
                    preIndex--;
                }
            } else  if (string.equalsIgnoreCase("delete"))  {
                if (nextIndex < stringLength) {
                    nextIndex++;
                }
            }
        }
        if (preIndex >= 0) {
            for (int i = 0; i <= preIndex; i++) {
                System.out.print(charArray[i]);
            }
        }
        System.out.print("I");
        if (nextIndex <= stringLength) {
            for (int i = nextIndex; i < stringLength; i++) {
                System.out.print(charArray[i]);
            }
        }
    }


}