#include <stdio.h>
#include <stdlib.h>
#include <math.h>

void main(void)
{
    void finddistances(int[][2], int, int[], int[]);
    void findtimes(int[], double[], int[], int, int[], int);
    void findmeetingpoint(int[][2], int[], double[], int[], int, int);

    char shipname[15][18] = {       //The names of each ship
                {"Bluenose"},
                {"France"},
                {"Repulse"},
                {"Golden Hind"},
                {"Hyperion"},
                {"Lusitania"},
                {"Hood"},
                {"Edmund Fitzgerald"},
                {"Titanic"},
                {"Andrea Dorea"},
                {"Queen Mary"},
                {"Queen Elizabeth"},
                {"Black Moxy"},
                {"Santa Maria"},
                {"Mary Celeste"}
                            };

    int doctor[15] = {1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1};
    //This array is a flag, specifying if there is a doctor on the ship,
    // corresponding with the elements of shipname.
    //  e.g. if element 1 has a 1, then the bluenose has a doctor..
    //   (1 = there is a doctor, 2 = there is not)



    int illpassenger[15] = {1, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0};

    //This specifies whether or not there is a sick passenger in the matching
    // location in the array, also corresponding with the shipname array, as above.





    int coord[15][2] =      {           //The x/y coordinates of each ship
                            {125 , 372},
                            {800 , 725},
                            {500 , 530},
                            {120 , 498},
                            {600 ,  58},
                            {650 , 890},
                            {400 , 687},
                            {280 , 715},
                            {510 , 650},
                            {89  , 802},
                            {784 , 410},
                            {900 , 945},
                            {176 , 750},
                            {200 , 178},
                            {200 ,  29}
                            };
    int *p;
    p = &coord[0][0];

    int speed[15] = {18, 32, 30, 17, 35, 35, 15, 16, 15, 35, 34, 28, 70, 10, 14};
    //This array specifies the speed of each ship, also corresponding with
    // the element in the shipname array, as the ill poassangers and doctors did.

    int distance[15] = {0};
    //The distance from the ship with the ill passenger to the other ships

    int meetpoint[2];
    //The point where the boat with the sick passenger will meet the boat
        //with the doctor

    int inneed,         //Index of the ship with an ill pasenger and no doctor.
        i,              //Used in loops
        closestship = 0;//This will mark the plce in the array of the closest
                                //ship weith a doctor

    double time[15] = {0};
    //The times to get from the ship with the ill passenger to the others;

    //Check each ship to see if there is an ill passenger and no doctor

    for(i = 0 ; i < 15 ; ++i)
        if(doctor[i] == 0 && illpassenger[i] == 1) //if there is no doctor, but an ill passenger
            inneed = i;                           //Mark the boat in need

    printf("Searching...     ");            //Just telling the user the program is searching...

    finddistances(coord , inneed , distance , doctor);
        //function to find/store the ditances to all the ships with doctors
        //                                           from the ill passenger

    findtimes(distance , time , speed , inneed , doctor, closestship);
        //function to find/store the time it takes to getthe ill pasenger
        //                                          to ships with doctors

    findmeetingpoint(coord , speed , time , meetpoint, closestship, inneed);
        //Function to find/store the meeting point of the ill passenger
        //                                   and the appropriate doctor

    /* Now that we have all the required information, we must work with it */

    printf("Information retreieved!\n\n");
    printf("Ship in need: %s\n", shipname[inneed]);
    printf("Closest ship with a doctor: %s\n", shipname[closestship]);
    printf("Distance between the ships: %d miles\n", distance[closestship]);
    printf("Ideal meeting point: %d , %d\n", meetpoint[0] , meetpoint[1]);
    printf("Time it will take for the ships to meet: %f\n",time[closestship]);



}


void finddistances(int coord[][2] , int inneed , int distance[], int doctor[])
{
    int i,  //for a loop
        a,  //Used for math arythmetic with the x coords
        b,  //Used for math arythmetic with the y coords
        c;  // hypotenuse. (c2 = a2 + b2)


    for(i = 0 ; i < 15 ; ++i)   //For each ship
        if(doctor[i] = 1)       //If there is actually a doctor...
        {
            //subtract the 2 y values, and the 2 x values, and square them (pythagerous).
            a = coord[inneed][1] - coord[i][1]; //set a to the distance between the x coords
            b = coord[inneed][2] - coord[i][2]; //same as above but with y coord
            a = pow(a , 2);                     //Set x to x to the power of 2
            b = pow(b , 2);                     //Set y to y to the power of 2
            c = a + b;                          //C NEEDS TO BE SQUARE ROOTED (c2 = a2 + b2)
            distance[i] = sqrt( c );            //Record the square root of c2 as the distance..
                                                    //... To that ship.
        }
}

void findtimes(int distance[] , double time[] , int speed[] , int inneed , int doctor[], int closestship)
{
    int i;                      //used for a loop.

    for(i = 0 ; i < 15 ; ++i)
    {
        if(distance[i] != 0)    //Due to the finddistance function, only the ships
                                //with doctors will have distances, and the rest will
                                //have the value 0, so eliminate these.

        time[i] = distance[i] / (speed[inneed] + speed[i]);
                                //take the distance to the current ship, and divide it
                                    //by the sums of the speeds of both ships
    }

    for(i = 0 ; i < 15 ; ++i)   //for each time
    {
        if(time[i] != 0)        //Excluding ships without doctors. ships without doctors wil;
                                        //have a value of 0 in the time array.
            closestship = 999;      //set this variable to a rediculously high number, that could not be
                                    //the shortest time.
            if(closestship > time[i])   //if the closestship variable is greater than the time to get to
                closestship = i;            //the ship we are currently looking at, set it to that number.
    }
}



void findmeetingpoint(int coord[][2] ,
                      int speed[] ,
                      double time[] ,
                      int meetpoint[],
                      int closestship,
                      int inneed)
{
    int i;                      //used for a loop

    /*
    ** In the following mathematic actions, it wil calculate the best meeting poit for the 2 ships.
    ** It will do this by a modified midpoint formula. (m = x1 * x2 / 2 , m = y1 * y2 /2)....
    ** It will find the x coordinate by taking the x coordinate of the ship in need, multiplying
    ** it by the speed of the other ship, and adding that to the x coordinate of the other ship multiplied
    ** by the speed of the ship in need. The sum of all this will be divided by the 2 combined speeds,
    ** to get the x coordinate. The same arythmetic will be done to find the y coordinate, but the x's
    ** replaced with y's.
    */

    meetpoint[0] = ( (coord[inneed][0] * speed[closestship]) + (coord[closestship][0] * speed[inneed]) )
                                        / (speed[inneed] + speed[closestship]);

    meetpoint[1] = ( (coord[inneed][1] * speed[closestship]) + (coord[closestship][1] * speed[inneed]) )
                                        / (speed[inneed] + speed[closestship]);
}