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Simulation - Stepping out of bounds?

jdwright (38)
I am writing a simulation program. In the code below I am using cout << action << endl; to test. I am getting some action results to be outside of the array. I cannot find, in my code, where the subscript is being blown.

Here is the entire program for reference:
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//
// Name: Jordan Fleming Wright
// Assignment: Random Walk
//

#include <iostream>
#include <cstdlib>
#include <ctime>
#include <iomanip>
using namespace std;

void fillArray (int ary[][14]);
void getMove (int step, int &r, int &c);
int getResult (int ary[][14], int r, int c, int action, int &complete, int &rescue);

int main()
{
    int island[13][14];
    int step, completed = 0, rescued = 0;
    int rPos = 6, cPos = 0, action = 0;
    int totalCost = 0;
    
    unsigned seed = time(0);
    srand (seed);
    
    fillArray (island);
    
    step = rand() % (100 + 1);
    getMove (step, rPos, cPos);
    action = island[rPos][cPos];
    while (action != 0)
    {
        step = rand() % (100 + 1);
        getMove (step, rPos, cPos);
        action = island[rPos][cPos];
    }
    
    //Start the simulation.
    for (int sim = 0; sim < 5000; sim++)
    {
        int cost = 0, action = 0;
        
        while (action >= 0 && action <= 2)
        {
            step = rand() % (100 + 1);
            //cout << step << endl;
            getMove (step, rPos, cPos);
            action = island[rPos][cPos];
            cout << action << endl;
            cost += getResult (island, rPos, cPos, action, completed, rescued);
        }
        
        totalCost += cost;
        
    }
    cout << totalCost << endl;
    
    cout << "The average cost of Harvey's walk: $" << (totalCost / 5000.0) << endl;
    cout << "The number of times Harvey made it to a bridge: " << completed << endl;
    cout << "The number of times Harvey had to be rescued: " << rescued << endl;
}

void fillArray (int ary[][14])
{
    //Water-------------------------//
    for (int c = 0; c < 14; c++)    //
    {                               //
        ary[0][c] = -1;             //
        ary[13][c] = -1;            //
    }                               //
                                    //
    for (int r = 1; r < 6; r++)     //
    {                               //
        ary[r][0] = -1;             //
        ary[r][13] = -1;            //
    }                               //
                                    //
    for (int r = 7; r < 12; r++)    //
    {                               //
        ary[r][0] = -1;             //
        ary[r][13] = -1;            //
    }                               //
    //------------------------------//
    
    //Footpath
    for (int c = 1; c < 13; c++)
    {
        ary[6][c] = 0;
    }
    
    //Flowers-----------------------//
    for (int r = 1; r < 6; r++)     //
    {                               //
        for (int c = 1; c < 13; c++)//
        {                           //
            ary[r][c] = 2;          //
        }                           //
    }                               //
                                    //
    for (int r = 7; r < 12; r++)    //
    {                               //
        for (int c = 1; c < 13; c++)//
        {                           //
            ary[r][c] = 2;          //
        }                           //
    }                               //
    //------------------------------//
    
    //Bridges
    ary[6][0] = 3;
    ary[6][13] = 3;
}

void getMove (int step, int &r, int &c)
{
    //Step forward
    if (c < 13)
    {
        if (step >= 0 && step <= 45)
        {
            c++;
        }
    }
    
    //Step right
    if (r < 12)
    {
        if (step > 45 && step <= 65)
        {
            r++;
        }
    }
    
    //Step left
    if (r > 0)
    {
        if (step > 65 && step <= 90)
        {
            r--;
        }
    }
    
    //Step back
    if (c > 0)
    {
        if (step > 90 && step <= 100)
        {
            c--;
        }
    }
}

int getResult (int ary[][14], int r, int c, int action, int &complete, int &rescue)
{
    int cost = 0;
    //Fell in water. Must be rescued.
    if (action == -1)
    {
        rescue++;
    }
    
    //Made it to one of the two bridges.
    if (action == 3)
    {
        complete++;
    }
    
    //Stepped on one of two flowers in a cell. Owes $5.
    if (action == 2)
    {
        cost = 5;
        ary[r][c]--;
    }
    
    //Stepped on the last flower in a cell. Owes $5.
    if (action == 1)
    {
        cost = 5;
        ary[r][c]--;
    }
    
    return cost;
}
jdwright (38)
So... anyone?
jlb (4973)
Here is one place:
ary[13][c] = -1;
You defined your array with a size of [13][14], remember arrays start at zero and stop at size - 1.

You also have a lot of "magic numbers" in your code, like the 13 in the above snippet, you should consider using constants instead.

And is there a reason you're using raw arrays instead of std::array or std::vector, or even a structure or a class?

jdwright (38)
Yep, I missed that one. Thank you.

The reason I hard coded so many numbers was just the nature of filling the array was very specific and I felt like there would be a ton of constants, but I may reconsider.

As far as the arrays, it's for a class and I'm just going by what my instructor has told us to do.
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