Finding in and out degrees of all vertices in a graph

Given a directed graph, the task is to count the in and out degree of each vertex of the graph.

Examples:

Input:
Example
Output:
Vertex    In    Out
0    1    2
1    2    1
2    2    3
3    2    2
4    2    2
5    2    2
6    2    1


Approach: Traverse adjacency list for every vertex, if size of the adjacency list of vertex i is x then the out degree for i = x and increment the in degree of every vertex that has an incoming edge from i. Repeat the steps for every vertex and print the in and out degrees for all the vertices in the end.

Below is the implementation of the above approach:

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// Java program to find the in and out degrees
// of the vertices of the given graph
import java.util.*;
  
class GFG {
  
    // Function to print the in and out degrees
    // of all the vertices of the given graph
    static void findInOutDegree(List<List<Integer> > adjList, int n)
    {
        int in[] = new int[n];
        int out[] = new int[n];
  
        for (int i = 0; i < adjList.size(); i++) {
  
            List<Integer> list = adjList.get(i);
  
            // Out degree for ith vertex will be the count
            // of direct paths from i to other vertices
            out[i] = list.size();
            for (int j = 0; j < list.size(); j++)
  
                // Every vertex that has an incoming 
                // edge from i
                in[list.get(j)]++;
        }
  
        System.out.println("Vertex\tIn\tOut");
        for (int k = 0; k < n; k++) {
            System.out.println(k + "\t" + in[k] + "\t" + out[k]);
        }
    }
  
    // Driver code
    public static void main(String args[])
    {
        // Adjacency list representation of the graph
        List<List<Integer> > adjList = new ArrayList<>();
  
        // Vertices 1 and 2 have an incoming edge 
        // from vertex 0
        List<Integer> tmp = 
           new ArrayList<Integer>(Arrays.asList(1, 2));
        adjList.add(tmp);
  
        // Vertex 3 has an incoming edge from vertex 1
        tmp = new ArrayList<Integer>(Arrays.asList(3));
        adjList.add(tmp);
  
        // Vertices 0, 5 and 6 have an incoming
        // edge from vertex 2
        tmp = 
          new ArrayList<Integer>(Arrays.asList(0, 5, 6));
        adjList.add(tmp);
  
        // Vertices 1 and 4 have an incoming edge 
        // from vertex 3
        tmp = new ArrayList<Integer>(Arrays.asList(1, 4));
        adjList.add(tmp);
  
        // Vertices 2 and 3 have an incoming edge
        // from vertex 4
        tmp = new ArrayList<Integer>(Arrays.asList(2, 3));
        adjList.add(tmp);
  
        // Vertices 4 and 6 have an incoming edge
        // from vertex 5
        tmp = new ArrayList<Integer>(Arrays.asList(4, 6));
        adjList.add(tmp);
  
        // Vertex 5 has an incoming edge from vertex 6
        tmp = new ArrayList<Integer>(Arrays.asList(5));
        adjList.add(tmp);
  
        int n = adjList.size();
        findInOutDegree(adjList, n);
    }
}

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Output:

Vertex    In    Out
0    1    2
1    2    1
2    2    3
3    2    2
4    2    2
5    2    2
6    2    1


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