public int Pop(int stackNum)
{
StackData stack = stacks[stackNum];
if (stack.size == 0)
{
throw new Exception("Trying to pop an empty stack.");
}
int value = buffer[stack.pointer];
buffer[stack.pointer] = 0;
stack.pointer = PreviousElement(stack.pointer);
stack.size--;
return(value);
}
public void Push(int stackNum, int value)
{
StackData stack = stacks[stackNum];
/* Check that we have space */
if (stack.size >= stack.capacity)
{
if (NumberOfElements() >= total_size)
{ // Totally full
throw new Exception("Out of space.");
}
else
{ // just need to shift things around
Expand(stackNum);
}
}
/* Find the index of the top element in the array + 1,
* /* and increment the stack pointer */
stack.size++;
stack.pointer = NextElement(stack.pointer);
buffer[stack.pointer] = value;
}
private void Shift(int stackNum)
{
StackData stack = stacks[stackNum];
// increase the capacity
if (stack.size >= stack.capacity)
{
int nextStack = (stackNum + 1) % number_of_stacks;
Shift(nextStack); // make some room
stack.capacity++;
}
// Shift elements in reverse order
for (int i = (stack.start + stack.capacity - 1) % total_size; stack.IsWithinStack(i, total_size); i = PreviousElement(i))
{
buffer[i] = buffer[PreviousElement(i)];
}
buffer[stack.start] = 0;
stack.start = NextElement(stack.start); // move stack start
stack.pointer = NextElement(stack.pointer); // move pointer
stack.capacity--; // return capacity to original
}
public bool IsEmpty(int stackNum)
{
StackData stack = stacks[stackNum];
return(stack.size == 0);
}
public int Peek(int stackNum)
{
StackData stack = stacks[stackNum];
return(buffer[stack.pointer]);
}