Linked list in Python
0
Below is my attempt at a doubly-linked list in Python (3):
class LinkedListNode:
def __init__(self, value):
self.value = value
self.left = None
self.right = None
class LinkedList:
def __init__(self):
self.head = self.tail = None
self.size = 0
def get_first(self):
if self.head:
return self.head.value
raise Exception('Reading from an empty list.')
def get_last(self):
if self.tail:
return self.tail.value
raise Exception('Reading from an empty list.')
def add_first(self, value):
node = LinkedListNode(value)
if self.head:
node.right = self.head
self.head.left = node
self.size += 1
else:
self.head = self.tail = LinkedListNode(value)
self.size = 1
def add_last(self, value):
node = LinkedListNode(value)
if self.tail:
node.left = self.tail
self.tail.right = node
self.size += 1
else:
self.head = self.tail = node
self.size = 1
def remove_first(self):
if self.head:
ret = self.head.value
self.head = self.head.right
self.head.left = None
self.size -= 1
return ret
raise Exception('Removing from an empty list.')
def remove_last(self):
if self.tail:
ret = self.tail.value
self.tail = self.tail.left
self.tail.right = None
self.size -= 1
return ret
raise Exception('Removing from an empty list.')
def __repr__(self):
str = '['
if self.size > 0:
str += self.head.value
node = self.head.right
while node:
str += ', ' + node.value
node = node.right
return str + ']'
def main():
list = LinkedList()
while True:
cmd_line = input()
if cmd_line == 'quit':
break
command_tokens = cmd_line.split()
command = command_tokens[0]
try:
if command == "get_first":
print(list.get_first())
elif command == "get_last":
print(list.get_last())
elif command == "add_first":
list.add_first(command_tokens[1])
elif command == "add_last":
list.add_last(command_tokens[1])
elif command == "remove_first":
list.remove_first()
elif command == "remove_last":
list.remove_last()
elif command == "print":
print(list)
except Exception:
print("Unknown command")
main()
How would I rewrite it in a professional manner?
python linked-list
asked 22 mins ago
coderoddecoderodde
15.7k538127
add a comment |
0
Below is my attempt at a doubly-linked list in Python (3):
class LinkedListNode:
def __init__(self, value):
self.value = value
self.left = None
self.right = None
class LinkedList:
def __init__(self):
self.head = self.tail = None
self.size = 0
def get_first(self):
if self.head:
return self.head.value
raise Exception('Reading from an empty list.')
def get_last(self):
if self.tail:
return self.tail.value
raise Exception('Reading from an empty list.')
def add_first(self, value):
node = LinkedListNode(value)
if self.head:
node.right = self.head
self.head.left = node
self.size += 1
else:
self.head = self.tail = LinkedListNode(value)
self.size = 1
def add_last(self, value):
node = LinkedListNode(value)
if self.tail:
node.left = self.tail
self.tail.right = node
self.size += 1
else:
self.head = self.tail = node
self.size = 1
def remove_first(self):
if self.head:
ret = self.head.value
self.head = self.head.right
self.head.left = None
self.size -= 1
return ret
raise Exception('Removing from an empty list.')
def remove_last(self):
if self.tail:
ret = self.tail.value
self.tail = self.tail.left
self.tail.right = None
self.size -= 1
return ret
raise Exception('Removing from an empty list.')
def __repr__(self):
str = '['
if self.size > 0:
str += self.head.value
node = self.head.right
while node:
str += ', ' + node.value
node = node.right
return str + ']'
def main():
list = LinkedList()
while True:
cmd_line = input()
if cmd_line == 'quit':
break
command_tokens = cmd_line.split()
command = command_tokens[0]
try:
if command == "get_first":
print(list.get_first())
elif command == "get_last":
print(list.get_last())
elif command == "add_first":
list.add_first(command_tokens[1])
elif command == "add_last":
list.add_last(command_tokens[1])
elif command == "remove_first":
list.remove_first()
elif command == "remove_last":
list.remove_last()
elif command == "print":
print(list)
except Exception:
print("Unknown command")
main()
How would I rewrite it in a professional manner?
python linked-list
asked 22 mins ago
coderoddecoderodde
15.7k538127
add a comment |
0
0
0
Below is my attempt at a doubly-linked list in Python (3):
class LinkedListNode:
def __init__(self, value):
self.value = value
self.left = None
self.right = None
class LinkedList:
def __init__(self):
self.head = self.tail = None
self.size = 0
def get_first(self):
if self.head:
return self.head.value
raise Exception('Reading from an empty list.')
def get_last(self):
if self.tail:
return self.tail.value
raise Exception('Reading from an empty list.')
def add_first(self, value):
node = LinkedListNode(value)
if self.head:
node.right = self.head
self.head.left = node
self.size += 1
else:
self.head = self.tail = LinkedListNode(value)
self.size = 1
def add_last(self, value):
node = LinkedListNode(value)
if self.tail:
node.left = self.tail
self.tail.right = node
self.size += 1
else:
self.head = self.tail = node
self.size = 1
def remove_first(self):
if self.head:
ret = self.head.value
self.head = self.head.right
self.head.left = None
self.size -= 1
return ret
raise Exception('Removing from an empty list.')
def remove_last(self):
if self.tail:
ret = self.tail.value
self.tail = self.tail.left
self.tail.right = None
self.size -= 1
return ret
raise Exception('Removing from an empty list.')
def __repr__(self):
str = '['
if self.size > 0:
str += self.head.value
node = self.head.right
while node:
str += ', ' + node.value
node = node.right
return str + ']'
def main():
list = LinkedList()
while True:
cmd_line = input()
if cmd_line == 'quit':
break
command_tokens = cmd_line.split()
command = command_tokens[0]
try:
if command == "get_first":
print(list.get_first())
elif command == "get_last":
print(list.get_last())
elif command == "add_first":
list.add_first(command_tokens[1])
elif command == "add_last":
list.add_last(command_tokens[1])
elif command == "remove_first":
list.remove_first()
elif command == "remove_last":
list.remove_last()
elif command == "print":
print(list)
except Exception:
print("Unknown command")
main()
How would I rewrite it in a professional manner?
python linked-list
asked 22 mins ago
coderoddecoderodde
15.7k538127
Below is my attempt at a doubly-linked list in Python (3):
class LinkedListNode:
def __init__(self, value):
self.value = value
self.left = None
self.right = None
class LinkedList:
def __init__(self):
self.head = self.tail = None
self.size = 0
def get_first(self):
if self.head:
return self.head.value
raise Exception('Reading from an empty list.')
def get_last(self):
if self.tail:
return self.tail.value
raise Exception('Reading from an empty list.')
def add_first(self, value):
node = LinkedListNode(value)
if self.head:
node.right = self.head
self.head.left = node
self.size += 1
else:
self.head = self.tail = LinkedListNode(value)
self.size = 1
def add_last(self, value):
node = LinkedListNode(value)
if self.tail:
node.left = self.tail
self.tail.right = node
self.size += 1
else:
self.head = self.tail = node
self.size = 1
def remove_first(self):
if self.head:
ret = self.head.value
self.head = self.head.right
self.head.left = None
self.size -= 1
return ret
raise Exception('Removing from an empty list.')
def remove_last(self):
if self.tail:
ret = self.tail.value
self.tail = self.tail.left
self.tail.right = None
self.size -= 1
return ret
raise Exception('Removing from an empty list.')
def __repr__(self):
str = '['
if self.size > 0:
str += self.head.value
node = self.head.right
while node:
str += ', ' + node.value
node = node.right
return str + ']'
def main():
list = LinkedList()
while True:
cmd_line = input()
if cmd_line == 'quit':
break
command_tokens = cmd_line.split()
command = command_tokens[0]
try:
if command == "get_first":
print(list.get_first())
elif command == "get_last":
print(list.get_last())
elif command == "add_first":
list.add_first(command_tokens[1])
elif command == "add_last":
list.add_last(command_tokens[1])
elif command == "remove_first":
list.remove_first()
elif command == "remove_last":
list.remove_last()
elif command == "print":
print(list)
except Exception:
print("Unknown command")
main()
How would I rewrite it in a professional manner?
python linked-list
python linked-list
asked 22 mins ago
coderoddecoderodde
15.7k538127
asked 22 mins ago
coderoddecoderodde
15.7k538127
asked 22 mins ago
coderoddecoderodde
15.7k538127
asked 22 mins ago
coderoddecoderodde
15.7k538127
asked 22 mins ago
coderoddecoderodde
15.7k538127
15.7k538127
add a comment |
add a comment |
0
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