#include <iostream>
#include <string>
#include <map> // for map<template>
#include <vector> 
#include <fstream> // for file io
#include <utility>
#include <cctype>
#include <algorithm> // for make_pair in map
#include <sstream> // for istringstream
using namespace std;


struct intersection {
	string road_one;
	string road_two;
};

struct neighbor {
	neighbor() { previous = -1; } // default constructor
	
	neighbor(intersection nb, double dis, double cs, int prev)
		: neighborToBe(nb), distance(dis), curSpeed(cs), previous(prev)
	{}

	intersection neighborToBe;
	double distance;
	double curSpeed;
	int previous; /* store index of vector<neighborMap>; 
				     eg: 0 refers to 1st St & 101st Ave intersection
					 eg: 12 refers to Freeway South @ 103rd Ave 
					 while -1 is undefined */
};

typedef map<intersection,neighbor> neighborMap;

class Graph {
public:

	/* vector< map<vertex, neighbor(neighborToBe, distance, curSpeed) */
	vector<neighborMap> graph_vector;
};

// declaration
	Graph g;

	neighborMap nbMap; // to be inserted into Graph object  (g)

	neighbor myNeighbor; // to be inserted into Graph object (g)

	vector<intersection> myInt_s; // to be inserted into neighbor object (myNeighbor) 
                                                  // and also neighborMap object (nbMap)   ->> this is when error will occur

	intersection ints; // is used to store various local intersection object
                                // and is to be inserted into vector of intersection (myInt_s)

	istringstream iss (line, istringstream::in); // to convert numbers in string to integers/doubles

        /* in some functions, i push several intersection objects into myInt_s within a loop*/
        /* below is the code snippet */

		string a = line.substr(0, int(amp)-1);
		string b = line.substr(int(amp)+2);
		ints.road_one = a;
		ints.road_two = b;

		myInt_s.push_back(ints);

         /* the above codes work find and i have tested the vector */

         /* then i read numbers from file using iss, which istringstream object 
             to build my neighbor object, which in turn will be inserted into neighborMap object */

                iss >> start >> end >> distance >> speed; // read numbers line
		myNeighbor.neighborToBe = myInt_s.at(end);
		myNeighbor.distance = distance;
		myNeighbor.curSpeed = speed; 

          /* then the Problem comes when I tried to insert one instance of intersection from 
           * vector myInt_s and a neighbor object into neighbor map object.
           * 
           * The following statement is supposed to get the instance of an intersection object 
           * at the 'start' position of vector myInt_s
           */

	nbMap.insert( make_pair(myInt_s.at(start), myNeighbor)); // ERROR
        g.graph_vector.push_back(nbMap);
							

// C2784.cpp
template<class T> class X {};
template<class T> void f(X<T>) {}

int main() {
   X<int> x;
   f(1);   // C2784

   // try the following line instead
   f(x);
}

//
// The predicate class used for the map so that objects will be
//  inserted in ascending order of key values
//
class compare_intersections
{
    public:
        bool operator() (const intersection & i1, const intersection & i2)
        {
         // 
         //  Implement something so that the function returns true if
         //  the value of i1 is to be considered less than the value
         //  of i2
         //
        }

};
.
.
.
.

typedef map < intersection, neighbor, compare_intersections > neighborMap;
.
.
.

while (numberOfRoadSegments != 0 && line.find("TRIPS") == string::npos) {
	istringstream iss (line, istringstream::in); // to convert numbers in string to integers/doubles
	// skip empty lines and lines with #
	if (line.find("#") != string::npos || line.empty())
		goto readAnotherLine;

	iss >> start >> end >> distance >> speed; // read numbers from string
							
	myNeighbor.neighborToBe = myInt_s.at(end);
	myNeighbor.distance = distance;
	myNeighbor.curSpeed = speed; 

	nbMap.insert( make_pair( myInt_s.at(start), myNeighbor));
	g.graph_vector.push_back(nbMap);
	cout << "size: " << nbMap.size() << endl;

	readAnotherLine:
		getline(inFile,line);
	}