I was solving this problem https://www.codechef.com/problems/COVERING and sort of came with a subproblem which is↵
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Given an array A and array B with size (2^N) . ↵
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Compute another array X of size (2^N) such that↵
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X[mask] = sum of (A[i] * B[j]) such that ( (i&j) == mask ) .↵
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How to solve it or is it solvable for N <= 20 .
Given an array A and array B with size (2^N) . ↵
[cut]↵
Compute another array X of size (2^N) such that↵
[cut]↵
X[mask] = sum of (A[i] * B[j]) such that ( (i&j) == mask ) .↵
[cut]↵
How to solve it or is it solvable for N <= 20 .