grep . dot meta character

commandline session

$ 4.2.20 37 537---> grep  rt  worked
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$ 4.2.20 38 538---> grep  p.rt  worked
$ 4.2.20 39 539---> grep  ..rt  worked
Bubble sort
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Insertion sort
Shell sort
Comb sort
Merge sort
Heapsort
Quicksort
Counting sort
 Bucket sort
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 Timsort
$ 4.2.20 40 540---> grep  s.rt  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 41 541--->