Thread: What is my mistake ?

i have coursework and i wrote the program but its not working ! can you help me about this

Assignment

Write a program for

-Creating a graph with n verticles and m edges.
-Counting the all isolated verticles in the graph

The Values of n and m are set by user.

The result should be shown appropriately on the screen of the computer.


And My Codes

Code:

// silinecek void edge_add code error
#include <iostream.h>
#include <stdlib.h>

const int v_n=10;
int i;
struct dgraph{ 
	char vertex;
    dgraph *gec;
}*gr[v_n];


int vertex_check(dgraph *gr[v_n], char ver){
	i=0;
	while(gr[i]){
		if(gr[i]->vertex==ver)
			return 1;
		i++;
	}
	return 0;
}

void vertex_add(dgraph *gr[v_n], char ver){
	if(vertex_check(gr,ver)==0){
		int y=0;
		while(gr[y] && (y<v_n))
			y++;
		gr[y]=new dgraph;
		gr[y]->vertex=ver;
		gr[y]->gec=NULL;
		cout << "\nVertex " << ver << " added.\n";
	}
	else
		cout << "\nError.";
}

bool edge_check(dgraph *gr[v_n], char ch1, char ch2){
	if((vertex_check(gr, ch1) && vertex_check(gr, ch2))==1){
		int say=0;
		while(gr[say]->vertex!=ch1)
			say++;
		dgraph *point=gr[say];
		while(point->vertex!=ch2 && point->gec!=NULL){
			point=point->gec;
			if(point->vertex==ch2)
				return true;
		}
	}
	return false;
}

void edge_add(dgraph *gr[v_n], char ch1, char ch2){
	if(edge_check(gr,ch1,ch2)==true)
		cout << "\nEdge exists.";
	else{
		if(vertex_check(gr,ch1)==0)
			vertex_add(gr,ch1);
		if(vertex_check(gr,ch2)==0)
			vertex_add(gr,ch2);
		dgraph *p;
		int gez=0;
		while(gr[gez]->vertex!=ch1)
			gez++;
		p=new dgraph;
		p->vertex=ch2;
		p->gec=gr[gez]->gec;
		gr[gez]->gec=p;
		cout << "\n\nEdge added: " << ch1 << "->" << ch2 << "\n";
		}
}

void yunus(){
	int a=0;
	while(gr[a]!=NULL){
		cout << "\n1\n";
		a++;
	}
}


void main(){
	int choice,vertices,edges,fa;
	int sayac=0;
	char vertex_name,edge_name1,edge_name2;
	cout << "Number of vertices:";
	cin >> vertices;
	cout << "\nNumber of edges:";
	cin >> edges;
	do{
		do{
		cout << "      \n\n[MENU]\n";
		cout << "1-> Add vertex\n";
		cout << "2-> Add edge between Vertex 1 & Vertex 2\n";
		//cout << "3-> List vertices with 3 out-degrees\n";
		cout << "4-> Exit\n";
		cout << "    Choice:";
		cin >> choice;
	}
	while(choice<1 && choice>4);
	switch(choice){
	case 1:
		for(fa=0;fa<vertices;fa++){
			cout << "\nVertex:";
	    	cin >> vertex_name;
	    	vertex_add(gr,vertex_name);
		}
			break;
	case 2:
		for(fa=0;fa<edges;fa++){
			cout << "\nVertex 1:";
			cin >> edge_name1;
			cout << "Vertex 2:";
			cin >> edge_name2;
			while(gr[sayac]->vertex!=edge_name1)
				sayac++;
			edge_add(&gr[sayac],edge_name1,edge_name2);
			sayac=0;
		}
			break;

	/*case 3:
		yunus();
		break;*/
	case 4: 
		exit(1);
	}
	}
	while(choice!=4);
}

its working but after the compiling when i start to add edges adn vertices i have an error

hi,
here the problem is exactly about the function "edge_add". because:
run the programme. then input 4 vertices : a,b,c,d. after that, begin inputting the edges:
a->b... ok.
b->a when you input this egde, you will see "vertex added." on the screen. now, we have 5 vertices in the array: a,b,c,d,a
that is the problem.

Originally Posted by anathex

hi,
here the problem is exactly about the function "edge_add". because:
run the programme. then input 4 vertices : a,b,c,d. after that, begin inputting the edges:
a->b... ok.
b->a when you input this egde, you will see "vertex added." on the screen. now, we have 5 vertices in the array: a,b,c,d,a
that is the problem.

Exactly thats a problem ! im sorry that my english is not very good! i cant translate that

???? anyone can help ????

Thanks Salem I will try again with like that