startup house warsaw logo
Case Studies Blog About Us Careers
What is Breadth-First Search (BFS)

what is breadth first search bfs

What is Breadth-First Search (BFS)

Breadth-First Search (BFS) is a fundamental graph traversal algorithm that explores all the vertices of a graph in breadth-first manner, systematically visiting each vertex and its adjacent neighbors before moving on to the next level of vertices. It is a widely used algorithm in computer science and is particularly useful for solving problems that involve finding the shortest path or exploring all possible paths in an unweighted or weighted graph.

The BFS algorithm starts by selecting an arbitrary vertex as the starting point and marks it as visited. It then explores all the adjacent vertices of the starting vertex and marks them as visited as well. This process continues layer by layer, exploring all the vertices at the current level before moving on to the next level. By doing so, BFS guarantees that it visits all the vertices in the graph, ensuring completeness.

One of the key advantages of BFS is its ability to find the shortest path between two vertices in an unweighted graph. This is achieved by maintaining a queue data structure that keeps track of the vertices to be visited. As BFS explores the graph, it enqueues the neighboring vertices of the current vertex, ensuring that the shortest path is found before exploring vertices at greater distances from the starting point. This property makes BFS an ideal choice for applications such as finding the shortest route in a transportation network or determining the fewest number of hops between two nodes in a network.

Furthermore, BFS can be extended to handle weighted graphs by incorporating a priority queue instead of a regular queue. This modification allows the algorithm to consider the weights of the edges and prioritize the exploration of vertices with lower weights, resulting in finding the shortest weighted path between two vertices.

In terms of time complexity, BFS traverses each vertex and its adjacent edges exactly once, making it an efficient algorithm with a time complexity of O(V + E), where V represents the number of vertices and E represents the number of edges in the graph. However, it is important to note that the space complexity of BFS can be significant, as it requires storing the visited vertices and the queue data structure, which can consume additional memory.

In conclusion, Breadth-First Search (BFS) is a versatile and powerful graph traversal algorithm that systematically explores all vertices of a graph in a breadth-first manner. Its ability to find the shortest path and explore all possible paths makes it a valuable tool in various applications, ranging from network routing to social network analysis. By understanding and utilizing BFS, developers and researchers can efficiently solve complex graph-related problems and optimize their algorithms for enhanced performance and accuracy. Breadth First Search (BFS) is a fundamental algorithm used in graph theory for traversing or searching tree or graph data structures. In BFS, the algorithm starts at a designated node and explores all of the neighbor nodes at the present depth prior to moving on to nodes at the next depth level. This approach ensures that all nodes at a given level are visited before moving on to the next level, hence the term "breadth first." BFS is particularly useful for finding the shortest path in an unweighted graph, as it guarantees the shortest path will be found as it explores all possible paths in a systematic manner.

One of the key advantages of using BFS is its simplicity and ease of implementation. The algorithm is well-suited for scenarios where the goal is to visit all nodes in a graph or tree in a systematic manner. Additionally, BFS can be used to determine the connected components of a graph, find the shortest path between two nodes, and check for the existence of a path between two nodes. By using a queue data structure to keep track of visited nodes, BFS ensures that nodes are visited in the order they were discovered, making it an efficient and reliable algorithm for a variety of graph traversal and search tasks.

In conclusion, Breadth First Search (BFS) is a versatile algorithm that plays a crucial role in graph theory and data structure analysis. By systematically exploring nodes at each level of a graph or tree, BFS can efficiently find the shortest path between two nodes, determine connected components, and search for a specific node within a graph. Its simplicity and effectiveness make BFS a valuable tool for a wide range of applications in computer science and data analysis.

We build products from scratch.

Company

Industries
startup house warsaw

Startup Development House sp. z o.o.

Aleje Jerozolimskie 81

Warsaw, 02-001

 

VAT-ID: PL5213739631

KRS: 0000624654

REGON: 364787848

 

Contact Us

Our office: +48 789 011 336

New business: +48 798 874 852

hello@startup-house.com

Follow Us

logologologologo

Copyright © 2026 Startup Development House sp. z o.o.

EU ProjectsPrivacy policy