Implement the following scenario in C++ along with the description of code and also write the steps and commands. Imagine you've got a toy that comes in two parts, and you need both parts to play with it—a toy drum and drumstick, for example. Now imagine that you've got two small children, both of whom like playing with it. If one of them gets both the drum and the drumstick, they can merrily play the drum until they get fed up. If the other child wants to play, they have to wait, however sad that makes them. Now imagine that the drum and the drumstick are buried (separately) in the toy box, and your children both decide to play with it at the same time, so go rummaging in the toy box. One finds the drum and the other finds the drumstick. Now they're stuck—unless the children are remarkably kind, each will hold onto whatever they've got and demand the other gives them the other bit, and neither gets to play. Now imagine that you've not got children arguing over toys, but threads arguing over locks on mutexes: each of a pair of threads needs to lock both of a pair of mutexes to perform some operation, and each thread has one mutex and is waiting for the other. Neither thread can proceed, as each is waiting for the other to release its mutex. This scenario is called deadlock and is the biggest problem with having to lock two or more mutexes in order to perform an operation. The common advice for avoiding deadlock is to always lock the two mutexes in the same order: if you always lock mutex A before mutex B, then you'll never deadlock. Sometimes this is straightforward, as the mutexes are serving different purposes, but other times it is not so simple, such as when the mutexes are each protecting a separate instance of the same class. Consider for example a comparison operation on two instances of the same class—in order to avoid the comparison being affected by concurrent modifications, the mutexes on both instances must be locked. However, if a fixed order is chosen (e.g. the mutex for the instance supplied as the first parameter, then the mutex for the instance supplied as the second parameter), then this can backfire: all it takes is for two threads to try and compare the same instances with the parameters swapped, and you've got deadlock!

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to run this in ubuntu open terminal in the same directory where you kept this cpp file OR you can na... View the full answer