在1<=n<=10000000个32位整数中选出最小的k个，输出依次为从大到小的最小的k个数字。计算时间2s内，内存使用小于12M。-In the 1 < = n < = 10000000 32-bit integers in a selected minimum k, the output in descending order of the minimum k digits. Calculating time 2s, memory usage is less than 12M.