i am trying to solve the problem https://www.hackerrank.com/challenges/tree-pruning/problem . the main point here is how to choice which subtree we have to delete and how dfs order to visit the node can help us ?
i am trying to solve the problem https://www.hackerrank.com/challenges/tree-pruning/problem . the main point here is how to choice which subtree we have to delete and how dfs order to visit the node can help us ?