help me deal with the problem

Question

I don't understand what happens at the 11 line
https://code.sololearn.com/cAWrq66gJISK/?ref=app

Answer 1

if a[j] == i:

a[j] is 'j' element of a list. 'j' is iterator in a loop line above.
'i' could be one of all possible values determined by loop 2 lines above (max. value is 'n').
If the statement is true(a[j] is equal i), print index of element and its value.