coldmanck

# -*-coding: utf-8-*-

def find_gpa(grade):
    if 100 >= grade >= 90:
        return [grade, 'A+', 4.3]
    elif 89 >= grade >= 85:
        return [grade, 'A', 4.0]
    elif 84 >= grade >= 80:
        return [grade, 'A-', 3.7]
    elif 79 >= grade >= 77:

coldmanck

Studying for a Tech Interview Sucks, so Here's a Cheat Sheet to Help

This list is meant to be a both a quick guide and reference for further research into these topics. It's basically a summary of that comp sci course you never took or forgot about, so there's no way it can cover everything in depth. It also will be available as a gist on Github for everyone to edit and add to.

Data Structure Basics

###Array ####Definition:

• Stores data elements based on an sequential, most commonly 0 based, index.
• Based on tuples from set theory.

coldmanck

def infectious_rabbit(grid):
    nb_of_timestamp = 0
    neighbors = [[1,0],[-1,0],[0,1],[0,-1]]
    updated = True
    while updated:
        updated = False # assume that after this infection there's no more neighbor rabbit to infect
        for i in range(len(grid)):
            for j in range(len(grid[0])):
                if grid[i][j] == 1: # for each healthy rabbit see if there's infectious rabbits nearby
                    for nb in neighbors: # for each of its neighbors

coldmanck

def combinationSum(self, candidates: List[int], target: int) -> List[List[int]]:
	cache = [[] for _ in range(target + 1)]
	cache[0] = [[]]
	for c in candidates:
		for i in range(target + 1):
			if i >= c:
				for temp_ans in cache[i - c]:
					cache[i].append(temp_ans + [c])
	return cache[-1]

coldmanck

def combinationSum(self, candidates: List[int], target: int) -> List[List[int]]:
	# BFS
	from collections import deque
	queue = deque() # [cur_target, cur_ans, cand_idx]
	queue.append((target, [], 0))
	ans = []
	while queue:
		cur_target, cur_ans, cand_idx = queue.popleft()
		for i in range(cand_idx, len(candidates)):
			new_target = cur_target - candidates[i]

coldmanck

def combinationSum(self, candidates: List[int], target: int) -> List[List[int]]:
	def combination_sum(cur_ans, cur_sum, cand_idx):
        if cur_sum >= target:
            if cur_sum == target:
                ans.append(cur_ans)
            return
        for i in range(cand_idx, len(candidates)):
            combination_sum(cur_ans + [candidates[i]], cur_sum + candidates[i], i)
	ans = []
	combination_sum([], 0, 0)