Java Program to Check the Connectivity of Directed Graph using DFS

This Java program,performs the DFS traversal on the given directed graph represented by a adjacency matrix to check connectivity.the DFS traversal makes use of an stack.

Here is the source code of the Java program to check the connectivity of a directed graph. The Java program is successfully compiled and run on a Linux system. The program output is also shown below.

import java.util.InputMismatchException;

```
import java.util.Scanner;
```
```
import java.util.Stack;
```
```
 
```
```
public class DirectedConnectivityDfs
```
```
{
```
```
    private Stack<Integer> stack;
```
```
 
```
```
    public DirectedConnectivityDfs() 
```
```
    {
```
```
        stack = new Stack<Integer>();
```
```
    }
```
```
 
```

    public void dfs(int adjacency_matrix[][], int source)

```
    {
```

        int number_of_nodes = adjacency_matrix[source].length - 1;

        int visited[] = new int[number_of_nodes + 1];

```
        int element = source;		
```
```
        int i = source;	
```
```
        visited[source] = 1;		
```
```
        stack.push(source);
```
```
 
```
```
        while (!stack.isEmpty())
```
```
        {
```
```
            element = stack.peek();
```
```
            i = element;	
```
```
	    while (i <= number_of_nodes)
```
```
	    {
```

     	        if (adjacency_matrix[element][i] == 1 && visited[i] == 0)

```
	        {
```
```
                    stack.push(i);
```
```
                    visited[i] = 1;
```
```
                    element = i;
```
```
                    i = 1;
```
```
	            continue;
```
```
                }
```
```
                i++;
```
```
	    }
```
```
            stack.pop();	
```
```
        }
```
```
        boolean connected = false;
```
```
 
```

        for (int vertex = 1; vertex <= number_of_nodes; vertex++)

```
        {
```
```
            if (visited[vertex] == 1) 
```
```
            {
```
```
                connected = true;
```
```
            }
```
```
            else
```
```
            {
```
```
                connected = false;
```
```
                break;
```
```
            }
```
```
        }
```
```
 
```
```
        if (connected)
```
```
        {
```

            System.out.println("The graph is connected");

```
        }else
```
```
        {
```

            System.out.println("The graph is disconnected");

```
        }
```
```
    }
```
```
 
```

    public static void main(String...arg)

```
    {
```
```
        int number_of_nodes, source;
```
```
        Scanner scanner = null;
```
```
 	try
```
```
        {
```

	    System.out.println("Enter the number of nodes in the graph");

            scanner = new Scanner(System.in);

            number_of_nodes = scanner.nextInt();

```
 
```

	    int adjacency_matrix[][] = new int[number_of_nodes + 1][number_of_nodes + 1];

	    System.out.println("Enter the adjacency matrix");

	    for (int i = 1; i <= number_of_nodes; i++)

	       for (int j = 1; j <= number_of_nodes; j++)

                   adjacency_matrix[i][j] = scanner.nextInt();

```
 
```

	    System.out.println("Enter the source for the graph");

            source = scanner.nextInt();

```
 
```

            DirectedConnectivityDfs directedConnectivity= new DirectedConnectivityDfs();

            directedConnectivity.dfs(adjacency_matrix, source);

```
 
```

        }catch(InputMismatchException inputMismatch)

```
        {
```

            System.out.println("Wrong Input format");

```
        }	
```
```
        scanner.close();	
```
```
    }	
```
```
}
```

$javac DirectedConnectivityDfs.java
$java DirectedConnectivityDfs
Enter the number of nodes in the graph
5
Enter the adjacency matrix
0 1 0 1 0
0 0 1 0 0
0 0 0 0 0
0 1 0 0 0
0 0 0 0 0
Enter the source for the graph
1
The graph is disconnected

Sanfoundry Global Education & Learning Series – 1000 Java Programs.

If you wish to look at all Java Programming examples, go to Java Programs.

If you find any mistake above, kindly email to [email protected]

« Prev - Java Program to Check the Connectivity of Undirected Graph using DFS

» Next - Java Program to Traverse a Graph using BFS

Related Posts:

Recommended Articles: