perl多关键字排序 perl逆序

trzxycx

perl多关键字排序 perl逆序
2012年01月19日
　　perl reverse sort {} map {} grep {} @a; sort comparator -1 1 0 不稳定排序(快速排序)
　　多关键字可以用：
　　$ka1$kb1
　　or $ka2$kb2
　　or $ka3$kb3
　　...
　　逆序输出可以用:
　　reverse
　　private static void mergeSort(Object[] src,
　　Object[] dest,
　　int low, int high, int off,
　　Comparator c) {
　　int length = high - low;
　　// Insertion sort on smallest arrays
　　if (length low && c.compare(dest[j-1], dest[j])>0; j--)
　　swap(dest, j, j-1);
　　return;
　　}
　　// Recursively sort halves of dest into src
　　int destLow  = low;
　　int destHigh = high;
　　low  += off;
　　high += off;
　　int mid = (low + high) >>> 1;
　　mergeSort(dest, src, low, mid, -off, c);
　　mergeSort(dest, src, mid, high, -off, c);
　　// If list is already sorted, just copy from src to dest.  This is an
　　// optimization that results in faster sorts for nearly ordered lists.
　　if (c.compare(src[mid-1], src[mid]) = high || p < mid && c.compare(src[p], src[q]) <= 0)
　　dest = src[p++];
　　else
　　dest = src[q++];
　　}
　　}