Reading a server log – Python Exercise with Solution

Summarise the lines of a server log.

What to build

A program that pulls structure out of raw lines of text.

Requirements

Each line has a date, a level and a message, separated by spaces. The message can contain spaces.
Print each level and its count, with the levels in alphabetical order.
Print First error: MESSAGE, or No errors if there are no lines with the level ERROR.

Input

The first line has n. Each of the next n lines is a log line.

Output

One line per level, then one more line.

Constraints

n is from 1 to 1000.

Example

Input:

3
2026-01-05 INFO server started
2026-01-05 ERROR disk full
2026-01-06 ERROR out of memory

Output:

ERROR 2
INFO 1
First error: disk full

Why it works

The limit in split(" ", 2) splits only twice, so the message keeps its own spaces. Sorting the dictionary's keys gives the alphabetical order.

Examples

Example 1 · Input

3
2026-01-05 INFO server started
2026-01-05 ERROR disk full
2026-01-06 ERROR out of memory

Expected output

ERROR 2
INFO 1
First error: disk full

Example 2 · Input

1
2026-02-01 WARN low battery

Expected output

WARN 1
No errors

Prompts inside input() are ignored when checking, so input("n: ") is fine.

Hints

Hint 1

Use line.split(" ", 2), so that the message stays in one piece.

Hint 2

Count each level in a dictionary.

Hint 3

Remember only the first error message you meet.

Solution

Show one correct solution (try it yourself first)

n = int(input())
counts = {}
first_error = None
for _ in range(n):
    date, level, message = input().split(" ", 2)
    counts[level] = counts.get(level, 0) + 1
    if level == "ERROR" and first_error is None:
        first_error = message
for level in sorted(counts):
    print(level, counts[level])
if first_error is None:
    print("No errors")
else:
    print("First error:", first_error)

Lesson: Processing text data →