Python和数据结构学习 --- 3

下面是使用Array实现Vector.也就是Python中自带的list().

代码如下:

class Vector:
    def __init__(self):
        self._length = 0
        self._capacity = 2
        self._array = Array(self._capacity)
        
    def __len__(self):
        return self._length
    
    def __contains__(self,item):
        for v in self:
            if v == item:
                return True
        return False
        
    def __getitem__(self,index):
        return self._array[index]
    
    def __setitem__(self,index,value):
        self._array[index] = value
        
    def __new_array(self):
        oldCap = self._capacity
        newCap = self._capacity * 2
        
        newArray = Array(newCap)
        for i,v in enumerate(self._array):
            newArray[i] = v
        self._array = newArray
        self._capacity = newCap       
    
        
    def append(self,item):
        if self._length == self._capacity:
            self.__new_array()
        self._array[self._length] = item
        self._length += 1
    
    def insert(self,ndx,item):
        if self._length == self._capacity:
            self.__new_array()
        for i in range(self._length,ndx,-1):
            self[i] = self[i-1]
        self._array[ndx] = item
        self._length += 1
    
    def remove(self,ndx):
        for i in range(ndx,self._length):
            self[i] = self[i+1]
        self._length -= 1
    
    def indexOf(self,item):
        for i,v in enumerate(self):
            if v == item:
                return i
        return -1
    
    def extend(self,otherVector):
        for v in otherVector:
            self.append(v)
    
    def subVector(self,f,t):
        newV = Vector()
        for i in range(f,t):
            newV.append(self._array[i])
        return newV
    
    def __iter__(self):
        return _VectorIterator(self)
    
    
class _VectorIterator:
    def __init__(self,theVector):
        self._vectorRef = theVector
        self._curNdx = 0
    def __iter__(self):
        return self
    def next(self):
        if self._curNdx < len(self._vectorRef):
            entry = self._vectorRef[self._curNdx]
            self._curNdx += 1
            return entry
        else:
            raise StopIteration

测试基本是跟list一样.

中间涉及到一个小东东.想要在Python隐藏函数,数据.只需要在前面加上`__`就可以了.当然数据,函数还在.只是换了一个名字而已.具体可以看<Python高级编程>(记得..).

 

睡觉先...