Single Source Shortest Path

import java.io.*;

class Graph

{   DataInputStream d=new DataInputStream(System.in);

                int e,v,g[][];

                void creategraph()throws IOException

                {

                                int a,b,i,j;int source,dest;

                                System.out.println("enter no of vertices");

                                v=Integer.parseInt(d.readLine());

                                System.out.println("enter no of edges");

                                e=Integer.parseInt(d.readLine());

                                g=new int[v+1][v+1];

                                for(i=1;i<=v;i++)

                                for(j=1;j<=v;j++)

                                g[i][j]=0;

                               

                                for(i=1;i<=e;i++)

                                {

                                                int w;

                                                System.out.println("enter two vertices of edge "+i);

                                                a=Integer.parseInt(d.readLine());