Problem	firstabc
User	lykieutrang
Submission Time	2025-10-24 17:10:55
Score	0
Max Time	N/A
Max Memory	N/A

Compile Error

firstabc.cpp:1:1: error: ‘N’ does not name a type
1 | N = input()
| ^
firstabc.cpp:10:23: error: expected unqualified-id before ‘.’ token
10 | if {'A', 'B', 'C'}.issubset(seen):
| ^