Given a graph G(V,E) as an adjacency matrix representation and a vertex, find the degree of the vertex v in the graph.

**Examples :**

0-----1 |\ | | \ | | \| 2-----3 Input : ver = 0 Output : 3 Input : ver = 1 Output : 2

Algorithm:-

1. Create the graphs adjacency matrix from src to des 2. For the given vertex then check if a path from this vertices to other exists then increment the degree. 3. Return degree

Below is the implementation of the approach.

## C++

// CPP program to find degree of a vertex. #include<iostream> using namespace std; // structure of a graph struct graph { // vertices int v; // edges int e; // direction from src to des int **dir; }; // Returns degree of ver in given graph int findDegree(struct graph *G, int ver) { // Traverse through row of ver and count // all connected cells (with value 1) int degree = 0; for (int i=0; i<G->v; i++) // if src to des is 1 the degree count if (G-> dir[ver][i] == 1) degree++; return degree; } struct graph *createGraph(int v,int e) { // G is a pointer of a graph struct graph *G = new graph; G->v = v; G->e = e; // allocate memory G->dir = new int*[v]; for (int i = 0;i < v;i++) G->dir[i] = new int[v]; /* 0-----1 | \ | | \ | | \ | 2-----3 */ //direction from 0 G->dir[0][1]=1; G->dir[0][2]=1; G->dir[0][3]=1; //direction from 1 G->dir[1][0]=1; G->dir[1][3]=1; //direction from 2 G->dir[2][0]=1; G->dir[2][3]=1; //direction from 3 G->dir[3][0]=1; G->dir[3][1]=1; G->dir[3][2]=1; return G; } // Driver code int main() { int vertices = 4; int edges = 5; struct graph *G = createGraph(vertices, edges); // loc is find the degree of // particular vertex int ver = 0; int degree = findDegree(G, ver); cout << degree << "\n"; return 0; }

## Java

// Java program to find degree of a vertex. class DegreeOfVertex { //Structure of Graph static class Graph { // vertices and edges int v, e; int[][] dir; //Graph Constructor Graph(int v, int e) { this.v = v; this.e = e; dir = new int[v][]; for (int i = 0; i < v; i++) dir[i] = new int[v]; } } static Graph createGraph(int v, int e) { Graph G = new Graph(v, e); /* 0-----1 | \ | | \ | | \ | 2-----3 */ //direction from 0 G.dir[0][1] = 1; G.dir[0][2] = 1; G.dir[0][3] = 1; //direction from 1 G.dir[1][0] = 1; G.dir[1][3] = 1; //direction from 2 G.dir[2][0] = 1; G.dir[2][3] = 1; //direction from 3 G.dir[3][0] = 1; G.dir[3][1] = 1; G.dir[3][2] = 1; return G; } static int findDegree(Graph G, int ver) { int degree = 0; for (int i = 0; i < G.v; i++) { if (G.dir[ver][i] == 1) degree++; } return degree; } // Driver code public static void main(String[] args) { int vertices = 4; int edges = 5; // Creating a Graph Graph G = createGraph(vertices, edges); int ver = 0; // Function calling int degree = findDegree(G, ver); System.out.println(degree); } }

Output:

3

// This code is contributed by rishabhdeepsingh98

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.

**Practice Tags :**