// Graph ADT interface ... COMP2521
#include <stdbool.h>

typedef struct GraphRep *Graph;

// vertices are ints
typedef int Vertex;

// edges are pairs of vertices (end-points)
typedef struct Edge
{
    Vertex v;
    Vertex w;
} Edge;

Graph newGraph(int);
void insertEdge(Graph, Edge);
void removeEdge(Graph, Edge);
bool adjacent(Graph, Vertex, Vertex);
void showGraph(Graph);
void freeGraph(Graph);

// By
//  .----------------.  .----------------.  .----------------.
//  .-----------------.  .----------------.  .----------------.
// | .--------------. || .--------------. || .--------------. ||
// .--------------. | | .--------------. || .--------------. | | |  _________ |
// || | _____  _____ | || |      __      | || | ____  _____  | | | |  ____  ____
// | || |     ____     | | | | |  _   _  |  | || ||_   _||_   _|| || |     /  \
// | || ||_   \|_   _| | | | | |_   ||   _| | || |   .'    `.   | | | | |_/ | |
// \_|  | || |  | |    | |  | || |    / /\ \    | || |  |   \ | |   | | | |   |
// |__| |   | || |  /  .--.  \  | | | |     | |      | || |  | '    ' |  | || |
// / ____ \   | || |  | |\ \| |   | | | |   |  __  |   | || |  | |    | |  | |
// | |    _| |_     | || |   \ `--' /   | || | _/ /    \ \_ | || | _| |_\   |_
// | | | |  _| |  | |_  | || |  \  `--'  /  | | | |   |_____|    | || | `.__.'
// | || ||____|  |____|| || ||_____|\____| | | | | |____||____| | || | `.____.'
// | | | |              | || |              | || |              | || | | | | |
// | || |              | | | '--------------' || '--------------' ||
// '--------------' || '--------------' | | '--------------' || '--------------'
// |
//  '----------------'  '----------------'  '----------------'
//  '----------------'   '----------------'  '----------------'

//  Email :    z5261243@unsw.edu.au
//             hhoanhtuann@gmail.com