Consider the following variant of the coordinated attack problem.
? Assume that the network is a complete graph of n>2 participants. The termination and validity requirements are the same as explained in the class. However, the agreement requirement is weakened to say: "If any process decides 1 then there are at least two that decide 1". That is, we want to rule out the case where one general attacks alone, but allow two or more generals to attack together. Is this problem solvable or unsolvable? Prove.
? Suppose now that the termination and agreement requirements are the same as explained in the class, but we have the following validity requirement: (a) If all processes start with 0, then no process decides 1. (b) If all processes start with 1, then no process decides 0. Is this problem solvable or unsolvable? Prove.
? Finally, suppose that the agreement and validity requirements are the same as explained in class, but the termination requirement is changed to: "If there are no message losses, then all processes eventually decide". Is this problem solvable or unsolvable? Prove.