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Problem Description​

Write a function that accepts a path to a log file on disk and returns the number of lines that start with “[ERROR]”. The log file could be as large as 10GB, but it may also not exist.

Input​

  • A string representing the path to a log file.

Output​

  • An integer representing the number of lines that start with “[ERROR]”.

Constraints​

  • The function should handle cases where the log file does not exist and return 0 in such cases.
  • The function should efficiently handle large files, potentially up to 10GB in size.

Example​

Example 1:

Input:
Log file: path/to/logfile.log
Contents of Log File:

[INFO] Information message
[ERROR] Error message 1
[INFO] Another information message
[ERROR] Error message 2

Output:
2

Explanation:
The log file contains 2 lines that start with “[ERROR]”.

Example 2:

Input:
Log file: path/to/logfile.log
Contents of Log File:

[INFO] Information message
[INFO] Another information message

Output:
0

Explanation:
The log file contains no lines that start with “[ERROR]”.

Example 3:

Input:
Log file: path/to/nonexistent.log
Contents of Log File: (File does not exist)

Output:
0

Explanation:
The log file does not exist, so the function returns 0.