Understanding the level order traversal pattern

The level order traversal starts from the top of the binary tree and processes all nodes from left to right in a level before doing the same for the subsequent level. Because all nodes of a level are processed before moving on to the next level, the level order traversal is ideal for solving problems where we need to apply some function on all nodes of a level, one level at a time. Moreover, since nodes at a level are processed from left to right, we also solve problems where the processing of subsequent nodes at a level depends on the processing of previous nodes at the same level.