Notes

#include <stdio.h>
#include<stdlib.h>
#include<string.h>

char **vertex;
int edge[4][4] ;

void addVertex(char *vname )
{
int i;
for ( i = 0; i < 4; ++i)
{
if(vertex[i] == NULL)
strcpy(vertex[i],vname);
}
}

void init()
{
int i,j;
for ( i = 0; i < 4; ++i)
{
if(vertex[i] == NULL)
vertex[i] = NULL;
}
for ( i = 0; i < 4; ++i)
{

for (j = 0; j < 4; ++j)
{
edge[i][j] = -1;
}

}

}

int findIndex(char *str)
{
int i;
for ( i = 0; i < 4; ++i)
{
if (strcmp(vertex[i],str))
{
return i;
}
}
return -1;

}

void addEdge(char *vname,char *vname2,int weight)
{
int i = findIndex(vname);
int i2 = findIndex(vname2);
if (i == -1 || i2 == -1)
{
return;
}
edge[i][i2] = weight;

}

int main()
{ int i,j;
char *arr[] = {"001","002","003","004"};
vertex = arr;
addEdge("002","002",1);
addEdge("001","004",1);
addEdge("002","003",1);
for ( i = 0; i < 4; ++i)
{
printf("%s ---->t",vertex[i] );
for (j = 0; j < 4; ++j)
{
if (edge[i][j]!= -1)
{
printf("%dt",edge[i][j] );
}
}
printf("n");
}
return 0;

}

// A C Program to demonstrate adjacency list
// representation of graphs
#include <stdio.h>
#include <stdlib.h>


struct AdjListNode
{
int dest;
struct AdjListNode* next;
};


struct AdjList
{
struct AdjListNode *head;
};


struct Graph
{
int V;
struct AdjList* array;
};

// A utility function to create a new adjacency list node
struct AdjListNode* newAdjListNode(int dest)
{
struct AdjListNode* newNode = (struct AdjListNode*) malloc(sizeof(struct AdjListNode));
newNode->dest = dest;
newNode->next = NULL;
return newNode;
}

// A utility function that creates a graph of V vertices
struct Graph* createGraph(int V)
{
struct Graph* graph = (struct Graph*) malloc(sizeof(struct Graph));
graph->V = V;

graph->array =
(struct AdjList*) malloc(V * sizeof(struct AdjList));

int i;
for (i = 0; i < V; ++i)
graph->array[i].head = NULL;

return graph;
}
void addEdge(struct Graph* graph, int src, int dest)
{
struct AdjListNode* newNode = newAdjListNode(dest);
newNode->next = graph->array[src].head;
graph->array[src].head = newNode;
newNode = newAdjListNode(src);
newNode->next = graph->array[dest].head;
graph->array[dest].head = newNode;
}

void printGraph(struct Graph* graph)
{
int v;
for (v = 0; v < graph->V; ++v)
{
struct AdjListNode* pCrawl = graph->array[v].head;
printf("n Adjacency list of vertex %dn head ", v);
while (pCrawl)
{
printf("-> %d", pCrawl->dest);
pCrawl = pCrawl->next;
}
printf("n");
}
}


int main()
{
// create the graph given in above fugure
int V = 5;
struct Graph* graph = createGraph(V);
addEdge(graph, 0, 1);
addEdge(graph, 0, 4);
addEdge(graph, 1, 2);
addEdge(graph, 1, 3);
addEdge(graph, 1, 4);
addEdge(graph, 2, 3);
addEdge(graph, 3, 4);

// print the adjacency list representation of the above graph
printGraph(graph);

return 0;
}