Perhaps cell2mat would work. or alternatively, adding square brackets to concatenate the cell contents:
L1 = [B{1,1}]
L2 = [B{2,1}]
Assigning the cells to individual variables (numbered or not) is not considered to be good programming practice in any event, so please avoid that if at all possible. Keep the elements of ‘B’ in an array of some description, and refer to the elements of the array instead.
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