FCFS.cpp

struct process{
	int id;
	int arrival;
	int burst;
};

queue<process> processes;


void first_come(){
	queue<process> ready_queue;
	bool running = false;
	bool idle = false;
	process p;
	int t = 0;
	int idle_time = 0;
	while(!processes.empty()){
		//put processes on the ready queue.
		while(processes.front().arrival == t){
			ready_queue.push(processes.front());
			processes.pop();
		}
		//Select a process to run.
		if(!running){
			//If the ready queue is empty, then we idle.
			if(ready_queue.empty()){
				if(!idle){
					cout << "Time " << t << " Idle" << endl;
				}
				idle = true;
				running = false;
				idle_time++;
			//If the ready queue is not empty, then we select the first
			//process from it.
			} else {
				idle = false;
				running = true;
				p = ready_queue.front();
				cout << "Time " << t << " Process " << p.id << endl;
				ready_queue.pop();
				p.burst -= 1;
			}
			t++;
		//If we're already running a process, wait for it to finish.
		} else {
			if(p.burst == 0){
				cout << "Process " << p.id << " finished at " << t << endl;
				running = false;
			} else {
				p.burst -= 1;
				t++;
			}
		}
	}
}