Time Limit: 2 Seconds
Memory Limit: 1024MB
Your best score: 0
Source: Codeforces Beta Round 11D

Subtask Score
1 1
2 1
3 2
4 2
5 4
6 4
7 4
8 4
9 4
10 4
11 7
12 7
13 7
14 7
15 7
16 7
17 9
18 9
19 10
20 0