Integer listSize is read from input, then listSize integers are read from input and stored in ArrayList tokensToPick. In formSequence$(),$ complete the recursive case to perform the following tasks:

Move the element at index i of remainTokens to the end of pickedTokens.

Recursively call formSequence$().$

Move the element from the end of pickedTokens back to index i of remainTokens.

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Ex: If the input is:

$3$

$71445$

then the output is:

All unique sequences:

$7+14=21$

$7+45=52$

$14+7=21$

$14+45=59$

$45+7=52$

$45+14=59$