jonathanagustin

const dgram = require('dgram');
const socket = dgram.createSocket('udp4');

//var port = 4242
//var port = 8087
var port = 18999

var address = "192.168.14.151"

var msg = '<?xml version="1.0" standalone="yes"?><event version="2.0" uid="J-01334" type="a-h-A-M-F-U-M" time="2005-04-05T11:43:38.07Z" start="2005-04-05T11:43:38.07Z" stale="2005-04-05T11:45:38.07Z"><detail></detail><point lat="30.0090027" lon="-85.9578735" ce="45.3" hae="-42.6" le="99.5"/></event>'

jonathanagustin

"""
https://www.algoexpert.io/questions/Two%20Number%20Sum

O(nlogn) time | O(1) space
This algorithm sorts the arrays and then puts two index 
pointers at the edges and then advances towards the 
middle to find a solution.
"""
def twoNumberSum(array, targetSum):
	# sort array (really a list) first

jonathanagustin

"""
https://www.algoexpert.io/questions/Find%20Closest%20Value%20In%20BST

Average: Theta(logn) time | Theta(logn) space 
Worst: O(n) time | O(n) space

This solution takes up O(n) space because of recursion.

float('inf') is used to set a unbounded upper value for comparison
"""

jonathanagustin

"""
https://www.algoexpert.io/questions/Branch%20Sums
"""

class BinaryTree:
    def __init__(self, value):
        self.value = value
        self.left = None
        self.right = None

jonathanagustin

"""
https://practice.geeksforgeeks.org/problems/finding-middle-element-in-a-linked-list/1

- Use "tortoise and the hare" method to find the middle
- Use a pointer that increments half the "speed" of another pointer
"""
def findMid(head):
    
    if head is None:
        return None

jonathanagustin

"""
https://practice.geeksforgeeks.org/problems/height-of-binary-tree/1

- use recursion to find the height
- use max on left and right branch on every recursion (add 1 every iteration)
"""
def height(root):
    if root is None:
        return 0
    return 1 + max(height(root.left), height(root.right))

jonathanagustin

Docker

Lessons Learned

/root/compile: line 2: $'\r': command not found

The above means you need to dos2unix the file.

Useful commands

jonathanagustin

"""
https://practice.geeksforgeeks.org/problems/inorder-traversal/1
"""
def InOrder(root):
  
    if root is None:
        return
    
    InOrder(root.left)
    

jonathanagustin

# Parallel sorting of lists

data = zip(list1, list2)
data.sort()
list1, list2 = map(lambda t: list(t), zip(*data))

jonathanagustin

"""
https://py.checkio.org/forum/post/9298/sorted-function-explanation-please/

This will sort a list of tuples by strings (second tuple item) 
and then by number in reversed order when strings are equal.
"""

list_of_tuples = [(1, 'a'), (1, 'b'), (2, 'a'), (2, 'b')]
list_of_tuples.sort(key=lambda t:(t[1], -t[0]))
print(list_of_tuples)