(c) The exchange machine instruction is defined as follows: void exchange (int register, int memory) { int temp; temp = memory; memory = register; register = temp; } It is assumed that it is implemented as an atomic instruction. Describe how exchange can be used to achieve mutual exclusion for n processes (e.g. by writ- ing a mutual exclusion procedure using pseudo-code). Explain whether your solution avoids busy waiting. (10 marks)