sec graph implementations /*graph adt *public interface graph /graph class adt /*initialize the graph @param the number of vertices *public void init(int )/*@return the number of vertices *public int ()/*@return the current number of edges *public int ()/*@return ' first neighbor *public int first(int )/*@return ' next neighbor *public int next(int vint )/*set the weight for an edge @param , the vertices @param wght edge weight *public void setedge(int iint jint wght)/*delete an edge @param , the vertices *public void deledge(int iint )/*determine if an edge is in the graph @param , the vertices @return true if edge , has non-zero weight *public boolean isedge(int iint )/*return an edge' weight @param , the vertices @return the weight of edge ,jor zero *public int weight(int iint )/*set the mark value for vertex @param the vertex @param val the value to set *public void setmark(int vint val)/*get the mark value for vertex @param the vertex @return the value of the mark *public int getmark(int )figure graph adt this adt assumes that the number of vertices is fixed when the graph is createdbut that edges can be added and removed it also supports mark array to aid graph traversal algorithms