快速排序

原文链接：http://blog.youkuaiyun.com/morewindows/article/details/6684558

void QuickSort(int *a,int l,int r){
    if(l < r){
        int i = l,j = r;
        temp = a[l];

        while(i < j){
            while(a[j] >= temp && i < j)
                j--;
                if(i < j)
                a[i++] = a[j];

            while(a[i] <= temp && i < j)
                i++;
                if(i < j)
                a[j--] = a[i++];
        }
            a[i] = temp;
            QuickSort(a,l,i - 1);
            QuickSort(a,i + 1,r);
    }

}