Problem 1439. USC Spring 2013 ACM: Building Snowmen

This Challenge is to solve the USC Spring 2013 ACM Contest Problem D, Building Snowmen

Summary of Challenge is determine maximum number of standard snowmen given N, 3<=N<=1000, snowballs of various integer diameter sizes. Standard snowman has Base >= 1.5 * Middle and a Middle >= 1.5 * Head. Diameter varies from 1 to 1000.

Return the maximum possible number of standard snowmen.

Input : 3 5 1 2 6 4 Output: 2

Input : 3 5 1 3 6 4 Output: 1

Matlab two line solution solves the 20 cases in 43 msec.

Competitor Gao's C Solution. Only Cao and Gao completed this challenge. Estimated time 100 minutes for Gao.

Solving without looking at the test suite is pretty tough.