Python Iterators and Generators Examples

🐍 Example 1: Create a generator that generates the squares of numbers up to some number N

def gensquares(N):

for x in range(N):

yield x**2

a = gensquares(10)

next(a)

Example 2: Create a generator that yields "n" random numbers between a low and high number (that are inputs)

import random

def rand_num(low,high,n):

    for x in range(n):

        yield random.randint(low,high)

y = rand_num(1,10,12)

next(y)

Example 3: Use the iter() function to convert the string below into an iterator

s = 'hello'

p = iter(s)

next(p)

Example 4: Example for Generator Comprehension

my_list = [1,2,3,4,5]

#The below line is a shortcut to create a generator

gencomp = (item for item in my_list if item > 3)

next(gencomp)

Comments

Python - List - Append, Count, Extend, Index, Insert, Pop, Remove, Reverse, Sort

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683 K Empty Slots

Approach #1: Insert Into Sorted Structure [Accepted] Intuition Let's add flowers in the order they bloom. When each flower blooms, we check it's neighbors to see if they can satisfy the condition with the current flower. Algorithm We'll maintain active , a sorted data structure containing every flower that has currently bloomed. When we add a flower to active , we should check it's lower and higher neighbors. If some neighbor satisfies the condition, we know the condition occurred first on this day. Complexity Analysis Time Complexity (Java): O(N \log N) O ( N lo g N ) , where N N is the length of flowers . Every insertion and search is O(\log N) O ( lo g N ) . Time Complexity (Python): O(N^2) O ( N 2 ) . As above, except list.insert is O(N) O ( N ) . Space Complexity: O(N) O ( N ) , the size of active . Approach #2: Min Queue [Accepted] Intuition For each contiguous block ("window") of k po...

Vinit Khandelwal

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