These three problems are almost the same.

CF618F [Double Knapsack]: https://mirror.codeforces.com/problemset/problem/618/F

CF1836E [Twin Cluster]: https://mirror.codeforces.com/contest/1836/problem/E

Beijing College Entrance Exam:

Given two positive integer arrays $$$A$$$ and $$$B$$$, such that:

$$$len(A) = len(B) = n$$$

and

for $$$\every 1 \leq i \leq n$$$, $$$1 \leq a_i, b_i \leq n$$$.