In this task, you are given inputs i,j, and A, where i and j are integers and A is a list. You need to concatenate all elements of A from the ith element to the jth element, and print the resultant string. i and j will be non-negative, and will always have a value less than the length of A. i will always be less than j.

Let me give you an example: 6, 14, ['9545', '5185', '1667', 'w', 's', '9559', 'T', 'u', 'U', '6843', 'L', 'l', '6365', '7103', 'A', '2381', '5037', 'X', '4487', 'd']
The answer to this example can be: 9559TuU6843Ll63657103
Here is why: Here, concatenating all the elements between the 6th element and 14th element gives '9559TuU6843Ll63657103'.

OK. solve this:
18, 20, ['6645', 'S', '8683', '8217', '7647', '6371', '8659', '607', '9635', 'U', 'f', 'w', '2053', 'o', 'o', 'f', '4041', '3419', '3467', 'O', '9311', '313', 'b', 'v', 'Q', '1591', '8809', 'l', '5621', '705']
Answer:
34193467O