Question

我正在尝试编写一个插入函数。但是我很迷茫。我有一个错误：

ValueError：无缘无故不在列表中。

我的代码：

def __init__(self):
    self.heap=[]
    self.size = 0
def parent(self,index):


    if index<=1:
        return None
    elif index>=self.size:
        return None
    else:
        return self.heap[int((index-1)/2)]

def swap(self, index1, index2):
    self.heap[index1-1], self.heap[index2-1] = self.heap[index2-1], self.heap[index1-1]

def insert(self,x):

    self.heap.append(x)
    self.size = self.size + 1
    #while currentsize :
        #if currentsize[x] > self.parent(self,x):
            #self.swap(currentsize[x],currentsize[int((x-1)/2)])
        #if x > self.parent(x):
            #self.swap((currentsize.index[x])+1, currentsize.index[self.parent(x)]+1)

    while self.heap.index(x)//2>0:
        if self.heap.index(x)>self.heap.index(self.parent(x)):
            #temp = a(x)
            #a.index(x//2) = a.index(x)
            #a.index(x) = temp
            self.swap(self.heap.index(x),self.heap.index(self.parent(x)))

Answer 1

您已经创建了self.size，但是忘记了从defs之外给它变量。我主要致力于使您的代码适用于parent()，并进行了一些脚本固定工作。我没有检查swap或insert defs，但是现在您掌握了它。

请参见另一个示例，如何在另一个问题的答案中使用self here。很多文档可以在其他地方找到。

以下代码打印：

lol [12, 13] 0    # <--- string, list, value
t1
(None, 1)

脚本：

def __init__(self, heap, size):
    self.heap = heap
    self.size = size
    print (type(self.size))

    print (self.size)

def parent(self, index):

    print ('lol', self, index)

    if index <= 1:
        print ('t1')
        return (None, 1)
    elif index >= x:
        print ('t2')
        return (None, 2)
    else:
        return self.heap[int((index - 1)/2)]

def swap(self, index_1, index_2):                   # Using underscore gives distinction between variable name (includes stringbased values) and real values. 
    self.heap[index_1 - 1], self.heap[index_2 - 1] = self.heap[index_2 - 1], self.heap[index_1 - 1]

def insert(self, x):

    self.heap.append(x)
    self.size = self.size + 1
    #while currentsize :
        #if currentsize[x] > self.parent(self,x):
            #self.swap(currentsize[x],currentsize[int((x-1)/2)])
        #if x > self.parent(x):
            #self.swap((currentsize.index[x])+1, currentsize.index[self.parent(x)]+1)

    hi =  self.heap.index(x)                        # < Reusable variable gives better readability of your script.

    while hi//2 > 0:

        hip = self.heap.index(self.parent(x))       # < Reusable variable gives better readability of your script.

        if hi > hip:
            #temp = a(x)
            #a.index(x//2) = a.index(x)
            #a.index(x) = temp
            self.swap(hi, hip)

if __name__ == "__main__":

    x = 12
    y = 13
    h = [x, y]    # <--- list heap
    s = 0         # <--- index size

    q = parent(h, s)
    print (q)     # < prints the returned result (checkmark 1 showns which "None" is returned.
    p = q[1]
    #print (p)    # printing p would give you '1' value.

插入最大二进制堆和ValueError

1 个答案: