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Oppiskele Shortest Path in Graph | Practice
Breadth First Search
course content

Kurssisisältö

Breadth First Search

Breadth First Search

1. What is BFS
2. Practice
3. Improve Your Code
4. Solving the Problems using BFS

book
Shortest Path in Graph

BFS searching shortest path

Well done! Now, let's implement a method that helps us to find the length of shortest path between two vertices, i. e. minimum number of edges to reach end vertice from start.

You should store the length of the way from start to curr node, and you can do it by modifying visited array: visited[i] equals:

  • -1, if i not visited yet

  • 0, if i is visited as first node

  • 1, if i is a neighbor of node, that has mark 0

  • k, if i is a neighbor of node with mark k-1 etc.

This way, you'll store the distance between start and current node, like at the example:

So, the answer is a visited[end].

Tehtävä

Swipe to start coding

bfs(start, end) returns a number of edges between start and end nodes. If there is no path, return -1.

Actually this method does traverse as BFT method, but until the end vertex is found. Copy & Paste your BFT algorithm, and add some changes.

Switch to desktopVaihda työpöytään todellista harjoitusta vartenJatka siitä, missä olet käyttämällä jotakin alla olevista vaihtoehdoista
Oliko kaikki selvää?

Miten voimme parantaa sitä?

Kiitos palautteestasi!

Osio 2. Luku 3
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book
Shortest Path in Graph

BFS searching shortest path

Well done! Now, let's implement a method that helps us to find the length of shortest path between two vertices, i. e. minimum number of edges to reach end vertice from start.

You should store the length of the way from start to curr node, and you can do it by modifying visited array: visited[i] equals:

  • -1, if i not visited yet

  • 0, if i is visited as first node

  • 1, if i is a neighbor of node, that has mark 0

  • k, if i is a neighbor of node with mark k-1 etc.

This way, you'll store the distance between start and current node, like at the example:

So, the answer is a visited[end].

Tehtävä

Swipe to start coding

bfs(start, end) returns a number of edges between start and end nodes. If there is no path, return -1.

Actually this method does traverse as BFT method, but until the end vertex is found. Copy & Paste your BFT algorithm, and add some changes.

Switch to desktopVaihda työpöytään todellista harjoitusta vartenJatka siitä, missä olet käyttämällä jotakin alla olevista vaihtoehdoista
Oliko kaikki selvää?

Miten voimme parantaa sitä?

Kiitos palautteestasi!

Osio 2. Luku 3
Switch to desktopVaihda työpöytään todellista harjoitusta vartenJatka siitä, missä olet käyttämällä jotakin alla olevista vaihtoehdoista
Pahoittelemme, että jotain meni pieleen. Mitä tapahtui?
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