List

The List with basic APIs:

boolean add(Object)
void add(Object, index)
Object remove(index)
int size()

class List:
    
    //data members
    int end//end element, zero-based
    Object[] list//array
    
    //constructors
    List():
        list = new Object[10] //default = 10
        end = -1
    
    List(int size):
        list = new Object[size]
        end = -1
    
    //methods
    boolean add(element):
        //return false if element does not satisfy certain conditions
        
        //increase array size if maxed out
        if list.length() = end+1 :
            //create new array and copy elements from current array
            sizeNew = getNewSize() //determine the new size
            listNew = new Object[sizeNew]
            for i = 0 to end :
                listNew[i] = list[i]
            list = listNew
            
        end++
        list[end] = element
        return true
        
    void add(element, index):
        if index > end :
            throw exception('out of bounds')
  
        //increase array size if maxed out
        if list.length() = end+1 :
            //create new array and copy elements from current array
            sizeNew = getNewSize() //determine the new size
            listNew = new Object[sizeNew]
            for i = 0 to end :
                listNew[i] = list[i]
            list = listNew
            
        //shift elements
        for int i = end down to index :
            list[i+1] = list[i] 
        
        end++
        list[index] = element
    
    Object remove(index):
        if end < 0 :
            throw exception('list empty')
        if index > end :
            throw exception('out of bounds')
        
        removedObject = list[index]
        //shift elements
        for int i = index to end-1 :
            list[i] = list[i+1]
        
        list[end] = null
        end--
        
        return removedObject
    
    int size():
        return end+1

[Hat tip to TL]