#include <iostream>
#include <cmath>
    
 //using namespace std; //  <===  works very badly
 //instead use the following
using std::cout;
using std::cin;
using std::endl;


#define MAX 100
#define MAXCITIES 1000

struct City {
	char name[MAX];
	double x,y;
};


// returns the moved city using a return statement
City moveCity(City city, int xmove, int ymove) {
	city.x = city.x + xmove;
	city.y += ymove;
	return city;
}


// returns the moved city as a reference parameter
void moveCity2(City &city, int xmove, int ymove) {
	city.x = city.x + xmove;
	city.y += ymove; 
}

// uses both techniques - possibly confusing!
City moveCity3(City &city, int xmove, int ymove) {
	city.x = city.x + xmove;
	city.y += ymove;
	return city;
}



City createMidPoint(City city1, City city2) {
	City midway;
	strcpy(midway.name, "Midway");
	midway.x = (city1.x + city2.x) /2;
	midway.y = (city1.y + city2.y) /2;
	return midway;
}



double distance(City c1, City c2) {
	return sqrt( pow(c1.x - c2.x,2) + 
		         pow(c1.y - c2.y,2) );
}


void findClosestCities(City cities[MAXCITIES], int cityCount,
				  City &city1, City &city2) {
    
	double minDist = distance(cities[0],cities[1]);
	city1 = cities[0];
	city2 = cities[1];
	
	for (int i = 0; i < cityCount; i++) {
		for (int j = i+1; j < cityCount; j++) {
			if (minDist > distance(cities[i],cities[j])) {
				minDist = distance(cities[i],cities[j]);
				city1 = cities[i];
				city2 = cities[j];
			}
		}
	}
	
}



int main() {
	
	City laramie;
	laramie.x = 0;
	laramie.y = 0;
	strcpy(laramie.name,"Laramie");

	City hiddenLaramie = laramie;

	City fortcollins = { "Fort Collins", 20,-45 };


	City cities[MAXCITIES];
	int cityCount;

	//.... fill these up
	cities[0] = laramie;
	cities[1] = fortcollins;
	cityCount = 2;



	cities[2] = createMidPoint(cities[0],cities[1]);
	cityCount++;

	cities[0] = moveCity(cities[0],40,-120);
	moveCity2(laramie,400,200);

	for (int i = 0; i < cityCount; i++) {
        cout << cities[i].name << " " 
			 << cities[i].x << " " 
			 << cities[i].y << endl;
	}

	City city1, city2;
	findClosestCities(cities,cityCount,city1,city2);
	cout << "Close cities" << endl;
	cout << city1.name << " and " << city2.name << endl;

}