code：

private boolean isUserIdHaveSameNum(String str) {
    int num = 5;
    char[] chars = str.toCharArray();
    int count = 0;
    for (int i = 0; i < chars.length - 1; i++) {
        if (chars[i] == chars[i + 1]) {
            count++;
        } else {
            count = 0;
        }
        if (count >= (num - 1)) {
            return true;
        }
    }
    return false;
}

输入：12888885
> true

输入：12234568
> false

输入：55555
> true