[Solved] Not Used Recently (NUR) Page Replacement Algorithm [closed]

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Usually Page Replacement Algorithms have a buffer and pages to put into the buffer.

Buffer size is fixed to a value say 4. Now we keep on adding pages into the buffer, If they are already in the buffer we ignore them and go for the next page to be inserted.

If they are not in the buffer. We have to insert into it if there is space. If there is no space then we search for a replacement element. In this case the least Frequently used.

How do we calculate the least frequently used?
Using a count array.

public class Demo {

public static void main(String[] args) {
    int size = 4;
    int []buffer = new int[size];
    int []bufferCount = new int[size];
    int[] pages = {1,2,3,4,5,1,2,1,2,3,4,6,1,2,1,5,1};
    int pos = 0;
    for(int i = 0; i < pages.length; i++)
    {
        System.out.print("For page: "+pages[i]+"\t");
        if((pos = contains(buffer, pages[i])) > 0)
        {
            //already in buffer increment the count
            bufferCount[pos] ++;
        }
        else
        {
            //choose the element with least usage and remove it
            int toRemove = getLeastUsed(bufferCount);
            bufferCount[toRemove] = 1;
            buffer[toRemove] = pages[i];
        }
        printBuffer(buffer);
        System.out.print("\t");
        printBuffer(bufferCount);
        System.out.println();
    }
}

private static void printBuffer(int[] buffer) {
    // TODO Auto-generated method stub
    for(int i = 0; i < buffer.length; i++)
        System.out.print(buffer[i] + "");
}

private static int getLeastUsed(int[] bufferCount) {
    // TODO Auto-generated method stub
    int index = 0;
    int min = bufferCount[0];
    for(int i = 0; i < bufferCount.length; i++)
        if(bufferCount[i] < min)
        {
            min = bufferCount[i];
            index = i;
        }
    return index;
}

private static int contains(int[] buffer, int key) {
    // TODO Auto-generated method stub
    for(int i = 0; i < buffer.length; i++)
        if(buffer[ i ] == key)
            return i;
    return -1;
}

}

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solved Not Used Recently (NUR) Page Replacement Algorithm [closed]