[Huawei OD Unified Exam B Paper | 200 points] Decompressing messages and restoring compressed messages (C++ Java JavaScript)

topic description

• In order to improve the efficiency of data transmission, the transmitted packets are compressed.
• Input a compressed message, please return its decompressed original message.
• Compression rule: n[str], means that the str inside the square brackets is repeated exactly n times.
• Note that n is a positive integer (0 < n <= 100), and str only contains lowercase English letters, regardless of abnormal conditions.

enter description

Enter the compressed message:

1) Regardless of invalid input, the message has no extra spaces, and the square brackets always meet the format requirements;

2) The original message does not contain numbers, and all numbers only represent the number of repetitions n, for example, there will be no input like 5b or 3[8];

output description

Original message after decompression

Note: The length of the original message will not exceed 1000, regardless of the abnormal situation

ACM input and output mode

If you often use Leetcode , you will know that letcode does not need to write input and output functions. However, the Huawei OD machine test uses the ACM mode , which requires manual programming of input and output.

So it is best to familiarize yourself with this mode in advance on Niu-ke. For example, C++ is used cin/cout, and python is used input()/print(). JavaScript uses node's readline()andcons