little elephant and balloons doubt

What should we print for 0/0 case? For example consider this case:

1

2 4

1 2

1 5

here number of possible subsets are zero and total cost is also zero.

This is not a possible as its clearly mentioned in the constrains of input

0 ≤ M ≤ K, where K is the number of different colors in the test
case.

Here in your case M=4 and K=1 as the number of different colors is one ( i and i )
So such a case would not come

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