public class Lru
{
	int numberOfPages;				//rozmiar pamięci wirtualnej - ilość stron
	int[] pages;
	int numberOfFrames;				//rozmiar pamięci fizycznej - ilość ramek
	int[][] frames;
	int[] stringReferences;			//ciąg odwołań

	public Lru(int numberOfPages, int numberOfFrames, int[] stringReferences)
	{
		this.numberOfPages = numberOfPages;
		this.numberOfFrames = numberOfFrames;
		this.stringReferences = stringReferences;
		this.pages = new int[numberOfPages];
		for(int i = 0; i < pages.length; i++)
			pages[i] = -1;
		this.frames = new int[numberOfFrames][2];
		for (int i=0; i<frames.length; i++)
				frames[i][0] = -1;
	}

	public void run()
	{
		int sumOfErrors = 0;
		int index = 0;
		for (int i=0; i<stringReferences.length; i++)
		{
			if (frames[numberOfFrames-1][0] == -1 && pages[stringReferences[i]] == -1)
			{
				sumOfErrors++;
				frames[index][0] = stringReferences[i];
				frames[index][1] = i;
				pages[stringReferences[i]] = index;
				index++;
			}
			else
			{
				if (pages[stringReferences[i]] == -1)
				{
					sumOfErrors++;
					index = 0;
					int lru = frames[0][1];
					for(int j=1; j<numberOfFrames; j++)
					{
							if (frames[j][1] < lru)
							{
								lru = frames[j][1];
								index = j;
							}
					}
					pages[frames[index][0]] = -1;
					frames[index][1] = i;
								frames[index][0] = stringReferences[i];
								pages[stringReferences[i]] = index;
				}
				else
				{
					frames[pages[stringReferences[i]]][1] = i;
				}
			}
		}
		System.out.println("Ilość błędów braku stron dla algorytmu LRU: "+sumOfErrors);
	}
}