Represent a graph using an adjacency list.

#include<stdio.h>
#include<stdlib.h>
 
typedef struct node {
	int vertexNumber;
	struct node * next;
} node;
typedef struct {
	int V;
	int E;
	node** Adj;  //array of linked list
} Graph;

Graph* adjacencyList() {
	int i, x, y;
	node * temp, *temp2;
	Graph* G=(Graph*) malloc(sizeof(Graph));

	printf("Enter the number of Vertices: ");
	scanf("%d", &G->V);
	printf("Enter the number of Edges: ");
	scanf("%d", &G->E);
	G->Adj = (node **)malloc(G->V * sizeof(node));
	for (i = 0; i < G->V; i++) {
		G->Adj[i] = (node *)malloc(G->V * sizeof(node));
		G->Adj[i]->vertexNumber = i;
		G->Adj[i]->next = NULL;
	}
 
	for (i = 0; i < G->E; i++) {
		printf("Enter the edge: ");
		scanf("%d %d", &x,&y);
		temp = (node*)malloc(sizeof(node));
		temp->vertexNumber = y;
        	temp->next = NULL;
        
		temp2 = G->Adj[x];
		while (temp2->next != NULL)
			temp2 = temp2->next;
		temp2->next = temp;
		
	}
	return G;
}

void test() {
	int u, v;
	Graph *G = adjacencyList();
	node * temp;
	for (u = 0; u < G->V; u++)
	{
		 
		do {
			printf("%4d\t", G->Adj[u]->vertexNumber);
			G->Adj[u] = G->Adj[u]->next;
		} while (  G->Adj[u]!=NULL);
 
		printf("\n");
	}
	 
}

int main()
{
	test();
	return 0;
}