
Problem Name 
Online Judge 
Year 
Contest 
Difficulty Level 
1 
ABCDEF 
SPOJ 


1 
2 
4 Values whose Sum is 0 
TJU 


1 
3 
Subset Sums 
SPOJ 


1 
4 
4 values whose sum is 0 
SPOJ 


1 
5 
4 Values whose Sum is 0 
Live Archive 
2005 
Europe  Southwestern 
1 
6 
Solitaire 
SPOJ 


2 
7 
Drazil and His Happy Friends 
Codeforces 

Codeforces Round #292 (Div. 1) & Codeforces Round #292 (Div. 2) & Codeforces Round #292 (Div. 1) & Codeforces Round #292 (Div. 2) 
2 
8 
Robbing Gringotts 
Live Archive 
2011 
Asia  Amritapuri 
2 
9 
The Morning after Halloween 
Live Archive 
2007 
Asia  Tokyo 
3 
10 
Vanya and Scales 
Codeforces 

Codeforces Round #308 (Div. 2) 
3 
11 
Face the mate 
SPOJ 


4 
12 
Parity 
SPOJ 


5 
13 
Inversions problem 
Codeforces 

Rockethon 2015 
5 
14 
Maximum Subsequence 
Codeforces 

Educational Codeforces Round 32 
5 
15 
Chocolate 
Codeforces 

Codeforces Round #279 (Div. 2) 
5 
16 
Golden System 
Codeforces 

MemSQL Start[c]UP 2.0  Round 2 
6 
17 
Anya and Cubes 
Codeforces 

Codeforces Round #297 (Div. 2) 
6 
18 
Permutation Sum 
Codeforces 

Codeforces Round #175 (Div. 2) 
6 
19 
Maximal Independent Set 
SPOJ 


6 
20 
Event Dates 
Codeforces 

School Team Contest #3 (Winter Computer School 2010/11) 
7 
21 
Lizard Era: Beginning 
Codeforces 

Codeforces Round #325 (Div. 1) & Codeforces Round #325 (Div. 2) 
7 
22 
Axis Walking 
Codeforces 

Codeforces Round #191 (Div. 2) 
7 
23 
EllysBulls 
TopCoder 

SRM 572  Div1 medium] (15492) 
7 
24 
Mother of Dragons 
Codeforces 

Codeforces Round #428 (Div. 2) 
8 
25 
The Morning after Halloween 
TJU 


8 
26 
Simplified Nonogram 
Codeforces 

Codeforces Round #298 (Div. 2) 
9 
27 
Missing Piece 2001 
TJU 


9 
28 
Permanent 
Codeforces 

Codeforces Round #268 (Div. 1) 
10 
29 
Wavy numbers 
Codeforces 

Codeforces Round #273 (Div. 2) 
10 