commandline session
$ 4.2.20 14 514---> grep '[bg]zip' worked $ 4.2.20 15 515---> grep '[bg]sort' worked $ 4.2.20 16 516---> grep '[b ]sort' worked Bubble sort Selection sort Insertion sort Shell sort Comb sort Merge sort Counting sort Bucket sort Radix sort Distribution sort $ 4.2.20 17 517---> grep '[b ]sort' worked Bubble sort Selection sort Insertion sort Shell sort Comb sort Merge sort Counting sort Bucket sort Radix sort Distribution sort $ 4.2.20 18 518---> cat worked Bubble sort Selection sort Insertion sort Shell sort Comb sort Merge sort Heapsort Quicksort Counting sort Bucket sort Radix sort Distribution sort Timsort $ 4.2.20 19 519--->