Pairwise understanding problem solved

Tell us what’s happening:
I gues, I don’t understand the Question.Why fourth expression should return 10 ?


best regards
Your code so far

solved … I considered indexing not the values…

Link to the challenge:

You can make two pairs of 0 and 1 (which sum to 1). By using the smallest available indices for the 0s, this the indexes you are summing are 0, 1, 4, and 5. 0+1+4+5 is 10.