DS4-version2.cpp

#include <cstdlib>
#include <iostream>
#include <string>
#include <fstream>
#include <algorithm>
#include <vector>

using namespace std;

typedef struct _node{
	string jobName;
	int priority;
	int length;
	friend bool operator<(const _node& x, const _node&y){
		return x.priority > y.priority;
	}
} node;
typedef node* pnode;

int main(int argc, char *argv[]){

	vector<node> pqueue;

	ifstream ifs;
	ifs.open("input.txt");

	if (ifs.is_open()){
		while (!ifs.eof())
		{
			pnode newNode = new node;
			ifs >> newNode->jobName >> newNode->priority >> newNode->length;
			pqueue.push_back((*newNode));
		}
	}
	else{
		cerr << "open file error!";
	}
	ifs.close();
	make_heap(pqueue.begin(), pqueue.end());
	sort_heap(pqueue.begin(), pqueue.end());
	cout << "%Current queue status:" << endl;
	
	int action;
	int cputime = 0;
	pnode pExecute = 0;
	cout << "%";
	for (unsigned int i = 0; i < pqueue.size(); i++){
		cout << pqueue[i].jobName << " ";
	}
	cout << endl << endl;

	while (true){
		cout << "For the following action," << endl;
		cout << "1.  execute" << endl;
		cout << "2.  insert a job" << endl;
		cout << "3.  quit" << endl;
		cout << "please select an action:  ";
		cin >> action;
		switch (action)
		{
		case 1:
			cout << endl;
			if (pqueue.size() != 0){
				cputime += pqueue.back().length;
				cout << pqueue.back().jobName << " finished at time " << cputime;
				make_heap(pqueue.begin(), pqueue.end());
				pop_heap(pqueue.begin(), pqueue.end()); 
				pqueue.pop_back();
			}
			cout << endl << endl;
			break;
		case 2:
			pExecute = new node;
			cout << "Your new job:" << endl;
			cin >> pExecute->jobName >> pExecute->priority >> pExecute->length;
			pqueue.push_back((*pExecute));
			cout << "%New queue status:" << endl;
			cout << "%";
			for (unsigned int i = 0; i < pqueue.size(); i++){
				cout << pqueue[i].jobName << " ";
			}
			cout << endl << endl;
			make_heap(pqueue.begin(), pqueue.end());
			sort_heap(pqueue.begin(), pqueue.end());
			break;
		case 3:
			while (true)
			{
				if (pqueue.size() != 0){
					make_heap(pqueue.begin(), pqueue.end());
					sort_heap(pqueue.begin(), pqueue.end());
					cputime += pqueue.back().length;
					cout << pqueue.back().jobName << " finished at time " << cputime;
					make_heap(pqueue.begin(), pqueue.end());
					pop_heap(pqueue.begin(), pqueue.end());
					pqueue.pop_back();
					cout << endl;
				}else{
					break;
				}
			}
			break;
		default:
			break;
		}
		if (action == 3) break;
	}
	system("PAUSE");
	return 0;
}