Need help with this bit manipulation problem

you are given a number N,you have to find the sum of f(i,j) for i starting from 1 to N and for each i, j starting from i to N.

ie;find from 1 to N Σ(from i to N Σf(i,j))

f(i,j)={ i*j if i&j =0, else 0}

here we’re given T test cases, 1<=T<=10 and 1<=N<=2*10^5

can you provide the question link

it was asked in a hiring contest. so unfortunately the question is not public.

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the first number j greater than i which will give i&j=0 is first power of 2 which is greater than i right?

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Here’s how I solved it today, hope you find it helpful.

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