Problème
Programs write log files with one event per line. Each line starts with a level word followed by a space and a message, for example ERROR disk full.
Given the lines of a log file, count the lines whose first word is exactly INFO, WARNING or ERROR. Lines that start with anything else (including lowercase levels) are ignored.
Implement count_log_levels(lines).
Input
lines: The lines of the file, without line breaks.
Output
Return [info_count, warning_count, error_count].
Contraintes
0 ≤ number of lines ≤ 10,000
Each line has at most 200 characters
Exemples
Entrée :
lines = ["INFO server started", "ERROR disk full", "INFO user login", "WARNING slow query"]
Sortie attendue :
expected = [2, 1, 1]
Entrée :
std::vector<std::string> lines = {"INFO server started", "ERROR disk full", "INFO user login", "WARNING slow query"};
Sortie attendue :
std::vector<long long> expected = {2, 1, 1};
Entrée :
string[] lines = new string[] {"INFO server started", "ERROR disk full", "INFO user login", "WARNING slow query"};
Sortie attendue :
long[] expected = new long[] {2, 1, 1};
Explication
Two lines start with INFO, one with WARNING and one with ERROR: [2, 1, 1].
Entrée :
lines = ["info lowercase", "DEBUG details", "ERROR"]
Sortie attendue :
expected = [0, 0, 1]
Entrée :
std::vector<std::string> lines = {"info lowercase", "DEBUG details", "ERROR"};
Sortie attendue :
std::vector<long long> expected = {0, 0, 1};
Entrée :
string[] lines = new string[] {"info lowercase", "DEBUG details", "ERROR"};
Sortie attendue :
long[] expected = new long[] {0, 0, 1};
Explication
"info" is not "INFO" and DEBUG is not counted. The last line is just the word ERROR, which counts: [0, 0, 1].
Comment l'aborder
Essayez d'abord seul, puis ouvrez les indices un par un.
Indice 1
Only the first word of each line matters.
Indice 2
Split once at the first space and compare that word exactly.
Indice 3
Case matters: "info" is not "INFO", and a line can be just the level word.
Complexité attendue
O(total length) time, O(1) extra space
Références
Ce défi a été adapté pour CodeUtility. Suivez l'énoncé et les contraintes ci-dessus.