I think it only takes 5 weighings when N=128. Am I incorrect?
agree 5 weighing for N=128 (worst case scenario you reduce to 43 15 5 2 1 after each consecutive weighing)
the last test case provided by the author is wrong: should be 5 since log(128)/log(3) < 5.
The problem is that the author do not specify an strategy. And as mentioned, dividing by 3 yields a better strategy than 6 weightings for 128. But, my guess is that the author counted the number of divisions instead of the number of weightings 128->[42 42 43] -> [14 14 14; 14 14 15]->[5 5 4; 5 5 5]->[2 2 0; 2 2 1]->[1;2]->1.
Correct the test suite
Find common elements in matrix rows
Penny flipping - calculate winning probability (easy)
Basic arrays operations.
Find the solution of algebraic equation
Generate pi using logarithm
Accessing elements on the diagonal
Reverse the elements of an array
Find out missing number from a vector of 9 elements
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