Shift The Matrix... n times!
the |||clickbait||| was to get you in here.
You have a rectangular matrix called m.
here's what one 'shift' looks like:
['a','b','c','d'] ['h','a','b','c']
['1','2','3','4'] => ['d','1','2','3']
['c','o','d','e'] ['4','c','o','d']
['b','l','a','h'] ['e','b','l','a']
another!
['d','u','d','e'] ['g','d','u','d']
['i','m','c','o'] => ['e','i','m','c']
['d','i','n','g'] ['o','d','i','n']
another!
['h','i'] ['k','h']
['o','k'] => ['i','o']
no empty matrices/dimensions will be passed in.