What is the difference between a breadth-first traversal and a depth-first traversal?

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What is the difference between a breadth-first traversal and a depth-first traversal?

The main difference between a breadth-first traversal and a depth-first traversal lies in the order in which the nodes of a graph or tree are visited.

In a breadth-first traversal, the nodes are visited level by level, starting from the root or a specified starting point. This means that all the nodes at the same level are visited before moving on to the next level. This traversal strategy explores the breadth or width of the graph or tree before going deeper. It uses a queue data structure to keep track of the nodes to be visited next.

On the other hand, in a depth-first traversal, the nodes are visited by exploring as far as possible along each branch before backtracking. This means that a path is followed until it reaches a leaf node or a node with no unvisited neighbors, and then the traversal backtracks to explore other branches. This traversal strategy explores the depth of the graph or tree before moving horizontally. It uses a stack data structure to keep track of the nodes to be visited next.

In summary, breadth-first traversal explores the graph or tree level by level, while depth-first traversal explores it branch by branch.