Given a set of cities and the costs to run power lines between them, calculate the minimum cost to connect all cities into a functioning power grid.

Find the minimum number of operations to reduce a given positive integer to 0. You can either subtract a power of 2 or add a power of 2 in each operation.

You're given a list of numbers. By deleting a number, you earn its value, but you must also delete all numbers one less and one greater than it. Maximize the total earned value.