1 
P1  Next Round 
Codeforces 
VK Cup 2012 Qualification Round 1 
2 
P2  Twins 
Codeforces 
Codeforces Round #111 (Div. 2) 
3 
P3  Gravity Flip 
Codeforces 
Codeforces Round #238 (Div. 2) 
4 
P4  Cut Ribbon 
Codeforces 
Codeforces Round #119 (Div. 2) 
5 
P5  Flipping Game 
Codeforces 
Codeforces Round #191 (Div. 2) 
6 
P6  Anatoly and Cockroaches 
Codeforces 
Codeforces Round #373 (Div. 2) 
7 
P7  Mahmoud and a Triangle 
Codeforces 
Codeforces Round #396 (Div. 2) 
8 
P8  4 values whose sum is 0 
SPOJ 

9 
P9  Interesting drink 
Codeforces 
Codeforces Round #367 (Div. 2) 