1. School of Mathematics, Statistics and Computer Science, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa
2. School of Computer Science, University of KwaZulu-Natal, King Edward Road, Pietermaritzburg Campus, Pietermaritzburg, KwaZulu-Natal 3201, South Africa
3. College of Computer Science, University of Hafr Al Batin, Saudi Arabia