hsbc test function

这个类用于移除连续三个或更多相同字符的字符串：
A
package com.example;

public class ConsecutiveRemover {
    public String removeConsecutive(String input) {
        if (input == null || input.isEmpty()) return input;

        StringBuilder sb = new StringBuilder(input);
        boolean changed;

        do {
            changed = false;
            for (int i = 0; i < sb.length() - 2; ) {
                if (sb.charAt(i) == sb.charAt(i + 1) && sb.charAt(i) == sb.charAt(i + 2)) {
                    char toRemove = sb.charAt(i);
                    int j = i;
                    while (j < sb.length() && sb.charAt(j) == toRemove) {
                        j++;
                    }
                    sb.delete(i, j);
                    changed = true;
                } else {
                    i++;
                }
            }
        } while (changed);

        return sb.toString();
    }
}



B
这个类用于替换连续三个或更多相同字符为它们前一个字母：
package com.example;

public class ConsecutiveReplacer {
    public String replaceConsecutive(String input) {
        if (input == null || input.isEmpty()) return input;

        StringBuilder sb = new StringBuilder(input);
        boolean changed;

        do {
            changed = false;
            for (int i = 0; i < sb.length() - 2; ) {
                if (sb.charAt(i) == sb.charAt(i + 1) && sb.charAt(i) == sb.charAt(i + 2)) {
                    char toReplace = sb.charAt(i);
                    char replacement = (char) (toReplace - 1);
                    int j = i;
                    while (j < sb.length() && sb.charAt(j) == toReplace) {
                        j++;
                    }
                    sb.replace(i, j, String.valueOf(replacement));
                    changed = true;
                } else {
                    i++;
                }
            }
        } while (changed);

        return sb.toString();
    }
}