Two cases have runtime error help me out
since n can be as large as 2,147,483,647 and when you are declaring ll int a[n+1]={0}; it generates run time error as we can’t make an array of the size as of the order 10^9.also your code complexity is o(n) so even if you could be saved using dynammic allocation you will eventually get TLE , because your idea of finding factors can be optimized further
refer this :-
and modify your code such that you can find all the factors in atleast o(sqrt(n))
you can refer to my code :-
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