Fake trees have been around for longer than you might think—but how do they compare to real trees when it comes to sustainability and your health? In some countries, artificial Christmas trees are ...

The US Capitol Christmas tree, named "Silver Belle", has been lit up during a ceremony on Tuesday. The 53-foot (16.15 meters) red fir was hand-selected from the Humboldt-Toiyabe National Forest, east ...

Mark Harmon crouches low next to log number 219: a moss-covered western hemlock tree trunk, five meters long, lying dead on the ground in the lush green woods. It’s marked by a thin aluminum tag. The ...

How do you count rooted planar n n-ary trees with some number of leaves? For n = 2 n = 2 this puzzle leads to the Catalan numbers. These are so fascinating that the combinatorist Richard Stanley wrote ...

Abstract: For increasingly complex real-world optimization problems, a large number of researches have shown that differential evolution (DE) is an effective problem-solving algorithm. Despite its ...

Now that we’re getting into more complex data structures, having more complex operations, it’s helpful to have a tool for visualization. Here’s a tool developed by David Galles, formerly of University ...

As climate change intensifies, the world’s oldest trees offer vital lessons in endurance and adaptation. From bristlecone pines of North America to the widely distributed sumaúma tree and more, each ...

Given the root of a binary tree, each node in the tree has a distinct value. After deleting all nodes with a value in to_delete, we are left with a forest (a disjoint union of trees). Return the roots ...