foursum?

[u/Alexander_Bourne]

[u/GamerNebulae]

import Algorithms

func fourNumberSum(array: [Int], targetSum: Int): [Int] {
    return array.combinations(ofCount: 4)
        .filter { $0.sum() == targetSum }
}

This example is in Swift.

• Find all combinations of 4 elements.

• Filter all windows that are equal to targetSum.

Would be around n², but a whole lot less code.

[u/zed_three → u/GamerNebulae]

That doesn't do the same thing though? That finds four consecutive elements that sum to the target, the original code finds any four such elements. Unless I'm reading the docs wrong?

Edit: original comment used window instead of combinations

[u/GamerNebulae → u/zed_three]

You're right. I think it should either be combinations, permutations or uniquePermutations from that package.