TopCoder problem "EggCartons" used in SRM 452 (Division II Level One)



Problem Statement

    There are two types of egg cartons. One type contains 6 eggs and the other type contains 8 eggs. John wants to buy exactly n eggs. Return the minimal number of egg cartons he must buy. If it's impossible to buy exactly n eggs, return -1.
 

Definition

    
Class:EggCartons
Method:minCartons
Parameters:int
Returns:int
Method signature:int minCartons(int n)
(be sure your method is public)
    
 

Constraints

-n will be between 1 and 100, inclusive.
 

Examples

0)
    
20
Returns: 3
He should buy 2 cartons containing 6 eggs and 1 carton containing 8 eggs. In total, he buys 3 egg cartons.
1)
    
24
Returns: 3
There are two ways to buy 24 eggs: buy 4 cartons containing 6 eggs or buy 3 cartons containing 8 eggs. Minimize the number of cartons.
2)
    
15
Returns: -1
He can't buy an odd number of eggs.
3)
    
4
Returns: -1

Problem url:

http://www.topcoder.com/stat?c=problem_statement&pm=10582

Problem stats url:

http://www.topcoder.com/tc?module=ProblemDetail&rd=13906&pm=10582

Writer:

rng_58

Testers:

PabloGilberto , connect4 , ivan_metelsky

Problem categories:

Brute Force