kingdido999

void mergeSort(int[] a, int[] b, int first, int last) {
  if (first < last) {
    int mid = (first + last) / 2;
    mergeSort(a, b, first, mid - 1);
    mergeSort(a, b, mid, last);
    merge(a, b, first, mid, last);
    copyBtoA(b, a, first, last);
  }
}

kingdido999

/* Inspired by: http://interactivepython.org/runestone/static/pythonds/SortSearch/TheQuickSort.html */

void quickSort(int[] a, int first, int last) {
  if (first < last) {
    int p = partition(a, first, last); // split point
    quickSort(a, first, p - 1); // sort numbers on the left side of the split point
    quickSort(a, p + 1, last); // sort numbers on the right side of the split point
  }
}

kingdido999

/*
 * CS460
 *
 * This will put a buffer into MRU list. This function should be only called by 
 * unpinning a buffer. Since it is MRU, we always put at head position. This
 * is consistent with StrategyGetBuffer where we pick also at head position.
 * This is not the same as InvalidateBuffer where a buffer is surely not useful
 * any more and should be put into free buffer instead.
 * 
 * MRU是将buf插入头部，LRU是将buf插入尾部