School of Computing, National University of Singapore, Building COM1, 117417 Singapore. donnysoh@gmail.com|School of Computing, National University of Singapore, Building COM1, 117417 Singapore. donnysoh@gmail.com|School of Computing, National University of Singapore, Building COM1, 117417 Singapore. donnysoh@gmail.com|School of Computing, National University of Singapore, Building COM1, 117417 Singapore. donnysoh@gmail.com