Computerscience April 2019 UG 15CCS2A 15CCA2A 15CCS4A_15CCA4B 15CCS6A 15CCA6A 15CCS6C_15CCA6C 15CCS6D 15CCA6D PG 16CPCS2A 16CPCS2B 16CPCS2C 16CPCS2D