SYSTEM-9 Posted on April 29, 2017 by ssmrmh Proposed by Daniel Sitaru-Romania SYSTEM-9 Solution 1 by Serban George Florin-Romania , Solution 2 by Rovshan Pirgulliyev-Sumgait-Azerbaidian , Solution 3 by Soumava Chakraborty-Kolkata-India , Solution 4 by Geanina Tudose-Romania