**Prim’s and Kruskal’s Algorithms-**

Before you go through this article, make sure that you have gone through the previous articles on **Prim’s Algorithm** & **Kruskal’s Algorithm**.

We have discussed-

- Prim’s and Kruskal’s Algorithm are the famous greedy algorithms.
- They are used for finding the Minimum Spanning Tree (MST) of a given graph.
- To apply these algorithms, the given graph must be weighted, connected and undirected.

Some important concepts based on them are-

**Concept-01:**

If all the edge weights are distinct, then both the algorithms are guaranteed to find the same MST.

**Example-**

Consider the following example-

Here, both the algorithms on the above given graph produces the same MST as shown.

**Concept-02:**

- If all the edge weights are not distinct, then both the algorithms may not always produce the same MST.
- However, cost of both the MST
_{s}would always be same in both the cases.

**Example-**

Consider the following example-

Here, both the algorithms on the above given graph produces different MST_{s} as shown but the cost is same in both the cases.

**Concept-03:**

Kruskal’s Algorithm is preferred when-

- The graph is sparse.
- There are less number of edges in the graph like E = O(V)
- The edges are already sorted or can be sorted in linear time.

Prim’s Algorithm is preferred when-

- The graph is dense.
- There are large number of edges in the graph like E = O(V
^{2}).

**Concept-04:**

Difference between Prim’s Algorithm and Kruskal’s Algorithm-

Prim’s Algorithm |
Kruskal’s Algorithm |

The tree that we are making or growing always remains connected. | The tree that we are making or growing usually remains disconnected. |

Prim’s Algorithm grows a solution from a random vertex by adding the next cheapest vertex to the existing tree. | Kruskal’s Algorithm grows a solution from the cheapest edge by adding the next cheapest edge to the existing tree / forest. |

Prim’s Algorithm is faster for dense graphs. | Kruskal’s Algorithm is faster for sparse graphs. |

To gain better understanding about Difference between Prim’s and Kruskal’s Algorithm,

**Next Article-** **Linear Search**

Get more notes and other study material of **Design and Analysis of Algorithms**.

Watch video lectures by visiting our YouTube channel **LearnVidFun**.