/// <summary>
/// This will create a number spiral
/// </summary>
/// <param name="maxNumber">The highest number to go to
/// in the spiral</param>
private NumberSpiral(int maxNumber)
{
this.maxNumber = maxNumber;
//Initialize the size of the array
arrayLength = (int)Math.Floor(Math.Sqrt(maxNumber) + 1);
spiralArray = new int[arrayLength, arrayLength];
//Initialize the array with vales of -1. This way it can be known what
//array elements are unoccupied and will assist with printing the spiral.
for (int y = 0; y < arrayLength; y++)
for (int x = 0; x < arrayLength; x++)
spiralArray[x, y] = -1;
//Find the starting indices
X_Index = (int)Math.Ceiling((double)arrayLength / 2) - 1;
Y_Index = X_Index;
//Initialize movement directions
X_Direction = X_Movement.Right;
Y_Direction = Y_Movement.NotMoving;
//Build the array
for (int currentNumber = 0; currentNumber <= maxNumber; currentNumber++)
{
spiralArray[X_Index, Y_Index] = currentNumber;
Move(currentNumber);
}
}
/// <summary>
/// This method moves the array indices to the next correct spot in
/// the spiral array
/// </summary>
/// <param name="currentNumber">The current number being written to
/// the spiral array</param>
private void Move(int currentNumber)
{
//If not at a turning point, simply move to the next
//position in the array
if (currentNumber != X_Multiplier * Y_Multiplier)
{
X_Index += (int)X_Direction;
Y_Index += (int)Y_Direction;
return;
}
//Otherwise this is a turning point - decide what to do next
//if moving in X, stop moving in X and change directions in Y
if (Y_Direction == 0)
{
if (X_Direction == X_Movement.Right)
{
Y_Direction = Y_Movement.Down;
}
else
{
Y_Direction = Y_Movement.Up;
}
X_Direction = X_Movement.NotMoving;
Y_Index += (int)Y_Direction;
X_Multiplier++;
return;
}
//Otherwise, stop moving in Y and change
//directions in X
if (Y_Direction == Y_Movement.Down)
{
X_Direction = X_Movement.Left;
}
else
{
X_Direction = X_Movement.Right;
}
Y_Direction = Y_Movement.NotMoving;
X_Index += (int)X_Direction;
Y_Multiplier++;
}
/// <summary>
/// This method moves the array indices to the next correct spot in
/// the spiral array
/// </summary>
/// <param name="currentNumber">The current number being written to
/// the spiral array</param>
private void Move(int currentNumber)
{
//If not at a turning point, simply move to the next
//position in the array
if (currentNumber != X_Multiplier * Y_Multiplier)
{
X_Index += (int)X_Direction;
Y_Index += (int)Y_Direction;
return;
}
//Otherwise this is a turning point - decide what to do next
//if moving in X, stop moving in X and change directions in Y
if (Y_Direction == 0)
{
if (X_Direction == X_Movement.Right)
Y_Direction = Y_Movement.Down;
else
Y_Direction = Y_Movement.Up;
X_Direction = X_Movement.NotMoving;
Y_Index += (int)Y_Direction;
X_Multiplier++;
return;
}
//Otherwise, stop moving in Y and change
//directions in X
if (Y_Direction == Y_Movement.Down)
X_Direction = X_Movement.Left;
else
X_Direction = X_Movement.Right;
Y_Direction = Y_Movement.NotMoving;
X_Index += (int)X_Direction;
Y_Multiplier++;
}