Can't resolve Segmentation Fault core dump error - c++

Question

I am writing a program that implements Dijkstra algorithm for graphs and I ran into this:
Segmentation fault (core dump). I have narrowed down the line (I have marked the line where the error is occurring) that is causing me the error, and then I used both GDB and Valgrind on my program, but all those told me was what line the error was occurring on, something I already new. Any help that y'all can give would me awesome! Thanks in advance!
////HERE'S MY MAIN/////
#include "Vertex.h"
#include <iostream>
#include <cstdlib>
#include <algorithm>
#include <vector>
#include <fstream>
using namespace std;
void Dijkstra(vector<Vertex> & V);
///overload the less than operator in order to use the stl sort for vector
///print out the path for each vertex
int main()
{
/////READ ALL THE STUFF INTO THE GRAPH////
ifstream file;
file.open("graph.txt");
cout << "Opening file..." << endl;
if(!file)
{
cout << "System failed to open file.";
}
else
{
cout << "File successfully opened" << endl;
}
int numVertices;
int numEdges;
int adjacentVertex;
int weight;
file >> numVertices;
cout << "The number of vertices that are being read into the graph from the file: " << numVertices;
cout << endl;
vector<Vertex*> vertices;
//vector<Vertex> vertices(numVertices + 1);
for(int i=1;i<=numVertices;i++)
{
file >> numEdges;
cout << "At vertex " << i << " the number of edges is " << numEdges << endl;
cout << "Hello" << endl;
vertices[i] = new Vertex(); ////THIS IS WHERE THE ERROR IS
cout << "World" << endl;
//Vertex newVertex;
//Using the i counter variable in the outer for loop to identify
//the what vertex what are currently looking at in order to read in the correct adjacent vertex and weight
vertices[i] -> setVertexNum(i);
//newVertex.setVertexNum(i);
for(int j=1;j<=numEdges;j++)
{
file >> adjacentVertex;
cout << "The adjacent vertex is: " << adjacentVertex << endl;
file >> weight;
cout << "The weight is: " << weight << endl;
cout << endl;
vertices[i]->setAdjacentVertex(adjacentVertex, weight);
}
vertices.push_back(vertices[i]);
}
file.close();
/*
for(int i=0;i<vertices.size();i++)
{
cout << "V" << i <<": ";
cout << endl;
for(int j=0;j<vertices[i].getAdjacentVertices().size();j++)
{
cout << "V" << vertices[i].getAdjacentVertices()[j].getAdjVertex() << " " << vertices[i].getAdjacentVertices()[j].getWeight() << endl;
}
}
*/
//CALL THE SHORTEST PATH FUNCTION ON THE GRAPH/////
}
////HERE'S MY VERTEX CLASS/////
#include "Edge.h"
#include <vector>
#include <climits>
#include <fstream>
using namespace std;
class Vertex
{
private:
int vertexNum; //number of the vertex for identification purposes
int degree;
bool known;
vector<Edge> adjacentVertices; //vector of vertices that are adjacent to the vertex we are currently looking at
int dv; //distance
int pv; //previous vertex
Vertex *vertex;
public:
Vertex()
{
dv = INT_MAX;
known = false;
}
void setKnown(bool Known)
{
known = Known;
}
bool getKnown()
{
return known;
}
void setVertexNum(int VertexNum)
{
vertexNum = VertexNum;
}
void setDegree(int Degree)
{
degree = Degree;
}
vector<Edge> & getAdjacentVertices()
{
return adjacentVertices;
}
int getVertexNum()
{
return vertexNum;
}
int getDegree()
{
return degree;
}
int getDV() const
{
return dv;
}
void setAdjacentVertex(int AdjacentVertex, int Weight)
{
Edge newEdge;
newEdge.setWeight(Weight);
newEdge.setAdjVertex(AdjacentVertex);
adjacentVertices.push_back(newEdge);
}
friend ostream & operator <<(ostream & outstream, Vertex & vertex)
{
outstream << vertex.vertexNum << endl;
outstream << vertex.degree << endl;
outstream << vertex.known << endl;
vector<Edge> E = vertex.getAdjacentVertices();
for(int x=0;x<E.size();x++)
{
outstream << E[x].getAdjVertex() << endl;
outstream << E[x].getWeight() << endl;
}
return outstream;
}
friend bool operator < (const Vertex & v1, const Vertex & v2);
void printVertex()
{
}
};

Answer 1

When initializing elements of a vector, you should use the push_back method.
So change:
vertices[i] = new Vertex();
to:
vertices.push_back( new Vertex() );
Of course, there are still other problems in your code. One hint I can give you is to iterate your for loops starting with 0 and using < instead of <= in the predicate.

Answer 2

So you must replace the line
vector <Vertex*> vertices;
By
vector<Vertex*> vertices(numVertices);