public float determineCellFitness() {
        float validCounter = 0;
        for (int cellIndexY = 0; cellIndexY < gridPower; cellIndexY++)
            for (int cellIndexX = 0; cellIndexX < gridPower; cellIndexX++)
                validCounter += (isCellValid(cellIndexX, cellIndexY)) ? 1 : 0;
        return validCounter / gridLength;
    }