43
Dmitry Khromenko
Last seen 34 minutes ago
Member for 3 years, 4 months, 17 days
Difficulty Normal
I study Python myself and help my son and daughter learn programming.
Initiation
sum + for
Count Digits
4
38
5
len - len
Beginning Zeros
4
33
3
split
Between Markers (simplified)
4
24
3
lambda
Nearest Value
6
48
6
classic
Acceptable Password I
6
25
4
lambda
Multiply (Intro)
8
35
5
max & set
The Most Frequent
8
19
4
classic
Is Even
8
16
2
yet another simple solution
Split Pairs
10
24
2
recursion
End Zeros
11
21
6
len + set
All the Same
11
17
2
sum map lambda
Sum Numbers
11
16
2
use slices
Replace First
12
18
2
classic
First Word (simplified)
16
13
3
findall regexp
Split Pairs
18
16
5
First
Easy Unpack
19
21
2
len str
Number Length
20
11
1
rstrip
Correct Sentence
29
13
3
simple
Max Digit
30
11
1
classic
Backward String
35
19
1
while loop
Remove All Before
37
10
2
use upper()
All Upper I
39
11
1
Home
math
Missing Number
1
33
9
sum, one line
Duplicate Zeros
2
14
1
diff sets
Missing Number
4
11
1
slices
Split List
5
23
1
clear maths
Sun Angle
6
22
6
one line, for in for
Duplicate Zeros
6
8
0
str replace one line
Duplicate Zeros
6
5
1
classic
Morse Decoder
7
29
1
heh
Date and Time Converter
8
18
0
zip + count
Changing direction
8
10
2
sum lambda, one line
Duplicate Zeros
8
6
1
join + split
Backward Each Word
12
13
4
find with sum
Missing Number
12
5
1
re.search
First Word
18
17
1
split + count
Popular Words
21
12
0
two key sorted
Sort Array by Element Frequency
29
15
2
something like this
Between Markers
29
11
1
generator
Duplicate Zeros
34
1
0
regex
Date and Time Converter
48
8
1
something like this
Second Index
55
9
2
using def
Pawn Brotherhood
68
32
0
datetime
Days Between
75
21
2
simple sorted
Bigger Price
84
8
1
join replace
Right to Left
124
16
4
re.search
Three Words
129
16
2
one string
Even the Last
132
17
3
Second Filter
Non-unique Elements
248
15
1
list filter
Non-unique Elements
344
11
1
Electronic Station
re and maketrans
Unix Match. Part 1
1
75
10
intersection method
Inside Block
2
26
0
one long string =)
Acceptable Password V
2
25
1
one string
Acceptable Password III
4
21
2
classic
Similar Triangles
5
27
3
5 strings
Acceptable Password VI
5
18
3
recursively paint over
Can You Pass?
5
15
2
one string
Acceptable Password IV
5
13
1
try except
Unix Match. Part 2
8
12
2
split into groups and recursion check
Mathematically Lucky Tickets
8
7
5
simple check
Acceptable Password II
9
15
0
6 lines solution
Remove Brackets
9
11
3
use dict
Surjection Strings
11
15
3
split + two key sorted
Sort by Extension
14
12
1
simple
Words Order
16
11
4
use any
Ascending List
16
11
2
with suppress
Unix Match. Part 2
22
4
1
use matrix diagonal and horizontal flip
Find Sequence
27
16
2
dictionary + lambda as a replacement for switch
Boolean Algebra
35
14
2
use queue
Brackets
93
14
1
three ways to solve - reduce, eval, recursion
Digits Multiplication
172
9
0
didn't think long
All Upper II
235
1
1
replace + lower + sorted
Verify Anagrams
497
2
1
Scientific Expedition
clear and readable
Convert and Aggregate
1
47
6
zip and split
Nonogram Encode
1
5
1
simple
Goes Right After
4
30
3
simple join
Caps Lock
5
16
0
Second
Sum by Type
5
8
1
max str
Latest ISO datetime
5
6
2
without re, 6 lines
Combining Celebrity Names
5
4
1
First
YAML. More Types
6
15
0
split + dict
YAML. Simple Dict
6
14
1
dict + lambda
Letter Queue
7
14
2
masochism?
Time Converter (24h to 12h)
7
7
1
First
Convert To Title Case
7
6
0
First
Longest Substring of Unique Characters
7
2
0
recursion
Count Substring Occurrences
8
3
0
BFS
Water Sort Game
8
0
0
dict + lambda (python way =)
Follow Instructions
9
21
0
First
Count Vowels
9
4
0
First
Fuzzy String Matching
12
2
0
7-liner, simple
Cipher Map
13
24
1
simple
Conversion into CamelCase
13
13
1
join + zip + sum
Sum by Type
15
11
2
First
Replace All Occurrences
17
1
1
simple
Morse Clock
19
16
1
hard way =)
The Hidden Word
19
10
5
it's a python the way? ;)
Time Converter (24h to 12h)
20
17
1
dict + lambda
The Most Wanted Letter
21
19
2
simple set
Pangram
25
21
1
unicodedata
Remove Accents
27
6
1
sorted split set
Common Words
31
19
2
heh, not so graceless
Conversion from CamelCase
35
9
1
First
Beat The Previous
37
0
0
lambda + set
Striped Words
72
7
1
simple
Call to Home
79
3
1
recursion with lambda (python way =)
Bird Language
124
8
1
First
I Love Python!
132
13
1
simple join
Secret Message
203
8
1
sorted with key
Absolute Sorting
217
8
1
O'Reilly
sum and recursion, one line
Sum of Digits
1
42
5
rectangles + combinations
Grid Painting
1
5
1
items count
Majority
2
52
4
array of lamps and array of event
Multiple Lightbulbs
2
12
1
recursion
Knapsack Problem
2
8
1
cut, merge and intersection (combination)
Lightbulb More
2
6
0
total_seconds()
Lightbulb Intro
3
29
0
strptime.strftime
Time Converter (12h to 24h)
4
40
1
simple
Replace Last
4
28
1
try except
Remove All After
4
21
1
build bridges recursively
Archipelago
4
0
0
one string solution with itertools combinations
Loading Cargo
5
18
3
First
Lightbulb Operating
5
6
0
use heapq
The Final Stone
6
9
3
divmod and recursion
Sum of Digits
7
7
1
add array of light
Lightbulb End Watching
7
5
0
while and sum
Sum of Digits
8
7
2
filter > start
Lightbulb Start Watching
9
12
1
two cycles
Flip of Time
9
0
0
recursion
How Deep
11
11
1
str and recursion
Integer Palindrome
11
5
1
while loop
Reverse Every Ascending
13
13
1
eval and recursion, one line
Sum of Digits
14
5
1
use median from statistics
Median of Three
15
8
0
f-string
The Hollow Diamond
18
0
1
First
String-2-Matrix
20
0
0
First
Matrix-2-String
20
0
0
permutations + dict
Cipher Crossword
24
1
1
First
Ordinary Cardinals
28
0
0
heh, not so graceless
Compress List
34
8
0
slice
Chunk
34
5
2
sorted with two keys
Frequency Sorting
35
8
0
sorted and pop
Sort Except Zero
40
5
0
operator and heapq
The Final Stone
52
0
1
two simple solutions
Count Inversions
88
4
1
First
Determine the Order
198
0
0
recursion
The Flat Dictionary
200
0
0
classic
Median
227
9
1
one string
Index Power
280
6
0
string replace
Flatten a List
284
4
2
flip tuple
Xs and Os Referee
308
4
1
Incinerator
classic
The Defenders
2
25
2
classic
The Vampires
5
8
1
classic
Army Battles
11
14
2
classic
The Warriors
24
14
3
First
Multicolored Lamp
29
8
2
Mine
recursion
Count Morse
1
22
0
First
Fibonacci Poem
1
14
3
formula
Toothpicks
1
13
2
recursion + cache
Cut Into Squares
1
5
2
Second
Ulam–Warburton Automaton
1
0
0
defaultdict
Switch Keys to Values
2
13
3
recursive
Count Morse
2
0
0
simple check
What Is Wrong With This Family?
3
35
3
First
Replace with Biggest
3
6
1
zip & set
Longest Common Prefix
3
3
0
DFS + recursion
Fast Train
4
10
1
while + pop
Matrix "Hatching"
4
2
1
recursion
Chess Knight
5
14
1
set & recursion
Ulam-Warburton Automaton Hex
6
6
1
repl as lambda in re.sub
Chemical Analysis
6
2
0
with recursion and set
Domino Chain
7
9
0
zip_longest, groupby, starmap
Long Pressed
7
0
0
First
Integer Sign Determination
8
6
1
regex 5 lines
Long Pressed
8
3
2
re, fullmatch, escape
Long Pressed
11
2
9
First
Achilles and the Tortoise
12
9
1
BFS for distance, first step for directions
Find Enemy
13
5
1
First
Rectangle Perimeter
13
4
0
regex
Adjacent Letters
15
3
0
escape
Escape
16
1
0
A147562(n) = A151920(2n-2), n >= 1
Ulam–Warburton Automaton
16
0
0
one string solution
Cut Sentence
17
9
1
clear and readable
Aggregate by Operation
17
2
1
First
Find Remainder
17
2
1
add zeros around of grid and sum slices
Moore Neighbourhood
18
16
1
recursion 5 lines
Disposable Teleports
21
4
0
First
Postfix Evaluation
21
0
0
get neibors and set color through recursion
Color Map
26
3
0
recursion
Number With Exclamation
37
0
0
math.gcd
The Greatest Common Divisor
38
7
1
First
The Greatest Common Divisor
44
6
0
slice + lambda
Can Balance
45
3
0
First
Best Stock
46
10
2
use permutation
Bigger Together
48
1
0
numpy
Determinant
68
0
0
only boolean
Fizz Buzz
103
26
0
use format
Binary Count
127
12
1
join and map
Caesar Cipher (encryptor)
167
3
0
filter, map and join
Caesar Cipher (decryptor)
197
0
0
Ice Base
Second
Is String a Number?
1
27
0
regex, 7 lines
Write Quadratic Equation
1
26
8
5 lines - sub + split + eval
Reveal the Number
1
24
2
First
Close Enough
1
5
1
recursive
Cleaning Robot
1
0
0
7-liner, recursion + frozenset
Count Chains
3
24
3
simple shift
Identify Block
4
10
3
1 line
Largest Rectangle in a Histogram
5
5
0
4 line - re.sub + split + eval
Reveal the Number
5
0
0
First
Is String a Number?
6
5
0
First
One Switch Strings
6
2
0
combinations_with_replacement
The Centrifuge Problem
6
0
1
clear maths
Oil Pie
7
7
1
count path
Cleaning Robot
9
0
0
1 line, sum
Monkey Typing
10
22
0
simple regex
Find Quotes
10
15
0
sorted
Move Zeros
10
5
1
First
When "k" is Enough!
10
4
0
for and items.count
Move Zeros
11
5
1
yield
Quadratic Equation Roots
20
0
0
1 line, classic
Morse Encoder
21
11
1
First
Leap Year Checking
23
1
0
First
Correct Capital
27
2
2
groupby
Count And Say
28
0
0
findall
Count And Say
29
0
0
First
Is String a Number? (Part II)
32
0
0
First
Perfect Number Checking
34
0
0
1 line, groupby + max
Long Repeat
36
10
1
First
Interesting, intersecting
38
0
0
First
Not in Order
39
0
0
5 lines, recursion
How to Find Friends
69
7
1
recursion with cache
Making Change
126
0
0
classic
The Most Numbers
156
10
2
classic
Feed Pigeons
201
3
0
First
Counting Tiles
256
0
0
classic
Clock Angle
260
0
0
Alice In Wonderland
clear
Bishop vs Aliens
1
3
1
recursion
YAML. Complex Structure
2
10
1
A250000
Peaceable Queens
2
8
1
determinant
Count Domino Tilings
5
0
0
1 line, clear math
Multiplication Table
6
15
3
classic
Middle Characters
6
15
1
while + for loops
Zigzag Array
6
11
0
simple recursion
Tree Walker
6
7
1
use previous solution, not optimize but take only 5 min
The Shortest Knight's Path
9
4
0
list zip
Transposed Matrix
16
8
1
count inversion
15-puzzle Solvability
16
0
0
sum tuple zip
Swap Nodes
17
10
0
First
Long Non Repeat
19
7
0
First
YAML. List and Comments
34
0
0
datetime strptime weekday
When is Friday?
35
5
1
GitHub
math sin cos
Searchlights
2
7
2
5 - liner, recursion in recursion =)
Simplify Unix Path
2
7
1
so so
Barcode Reader
4
5
0
minimax algorithm
Xs and Os Champion
6
1
0
Simple Recursion :-)
The Cheapest Flight
7
12
1
1 line - dict split strip
Cookies
8
11
1
First
The End of Other
9
13
1
use bfs to find the paths, roll and mark cube
Paper Dice
10
1
0
8 lines
Power Supply
11
5
0
Gauss's area formula
Area of a Convex Polygon
18
6
1
merge and summ
Painting Wall
18
5
1
First
Shooting Range
20
3
0
works but ugly
Power Plants
26
0
0
regex in loop, 8 lines
Simplify Unix Path
28
1
2
First
Create Intervals
30
5
2
set + range
The Most Frequent Weekdays
33
7
2
zip(*buildings)
The Highest Building
35
5
1
First
Solution for Anything
73
3
0
recursion + combinations
Long Repeat Inside
80
1
2
diff + gcd
Evenly Spaced Trees
84
0
1
range + sum
Expand Intervals
96
2
1
classic dfs throw recursion
Open Labyrinth
129
4
0
classic
Broken Clock
130
0
0
First
Merge Intervals
160
0
1
Dropbox
First
Grille Cipher Attack
1
5
1
str & int
Armstrong Number Checking
4
7
0
First
Calculator-I
6
6
0
brute force
Hubspot Amulet
6
6
0
First
Tricky String
7
3
0
hashlib.new
Simple Hashlib
8
14
2
simple recursion
On the same path
8
5
0
combinations
Count Squares
10
0
0
max, key, default
The Longest Word
12
2
1
First
Worth of Words
13
10
1
First
Reverse Integer
13
5
0
queue
e+pi
13
0
0
try pop ellipsis
Common Tail
14
3
1
3 if
Frogs Collision
16
0
0
recursion + sets
Place Queens
18
1
0
First
All Permutations
19
0
0
transform with dict
Atbash Cipher
20
3
0
simple math
Count Divisibles in Range (simplified)
20
0
0
First
Scytale Encryption
21
2
2
recursion and compare as tuple
Huffman Encode
21
0
0
classic
Numbers Factory
22
15
2
yield + stack
Revorse the vewels
22
0
0
First
Maximum Among Three
23
0
1
First
Sort Sorted Groups
23
0
0
classic
The Longest Palindromic
27
14
1
clear maths
Three Points Circle
27
9
0
takewhile
Common Tail
28
0
2
First
Rotating Grille Cipher
29
0
0
recursion
Sum of Integers
29
0
0
recursion
Nonogram Row
34
0
0
First
Humpty Dumpty Form
38
5
0
regex
URL Normalization
54
0
0
First
Text Formatting
84
0
1
phi number, golden ratio
The Best Number Ever
201
0
1
heh
Speech Module
373
3
1
Third
The Best Number Ever
615
0
0
PyCon TW
First
Building Visibility
11
0
0
bubble sort
Robot Sort
18
3
0
Second
Ryerson Letter Grade
26
4
0
numpy linalg
How Much Gold
27
0
0
match case
Simple Areas
59
5
1
inverted pyramid and sum
Golden Pyramid
64
5
1
second
Double Substring
71
3
0
First
Ryerson Letter Grade
124
0
1
groupby
Sum Consecutives
154
0
0
First
House Password
302
6
1
re findall
Double Substring
309
0
0
recursion
Calculate Islands
331
0
0
First
Network Attack
356
0
0
First
Digit Stack
634
0
0
Storage
First
Working Hours Calculator
2
7
1
First
Square Spiral
10
5
0
__mod__
Restricted Prime
14
6
1
join + int(,2)
Word Pattern
16
5
1
First
List Beautify
25
0
0
doubled hexagonal coordinates
Hexagon Spiral
33
0
0
groupby
Group Equal consecutive
51
5
0
simple
Playfair Cipher
108
0
0
First
Skew-symmetric Matrix
134
4
0
lambda + zip
Weak Point
602
0
0
Maya
move cube to colored cell and collect with bfs nearby colored cells
Roll the cube
2
5
0
HubSpot
binary search
Workout
4
4
0
rotate with numpy
Inscribe a Contour
5
0
0
First
Node Disconnected Users
6
9
1
bfs
Triangular Islands
8
5
0
0x66666667 - magic number
Univocalic davasaan
13
4
1
datetime timedelta
Weekly Calendar
15
3
1
6 lines solution
Node Disconnected Users
19
5
0
bfs and set
Supply Line
26
2
1
Second
Team Play
37
0
0
5 lines, recursion
New Cities
52
1
1
First
Square Board
65
0
0
strange solution with sets
City's Happiness
85
0
0
First
Repeating Decimals
104
0
0
try except
Number Base
124
15
1
First
Auto Painting
136
0
0
len set map
Non Empty Lines
137
0
0
eval
Restricted Sum
222
5
1
clear
The Hamming Distance
257
3
1
Blizzard
convert to x-axis coordinates and remove intersections
Mountain Scape
3
5
0
recursion
Sudoku Solver
7
5
2
First
Palindromic Palindrome
12
5
0
4 lines, regular expression safe us :-)
Stressful Subject
13
16
7
recursion
Checkers Capture
13
0
0
point sum
Rectangles Union
17
6
0
1 line, recursion
Stair Steps
20
7
0
use factorial number system
Permutation Index
21
3
1
datetime timedelta strftime strptime
The First Working Day
23
5
1
recursion, 1 line
Stair Steps
27
0
0
Prim's algorithm
Connect Stars
38
0
0
BFS
Useless Flights
50
0
0
dijkstra
Useless Flights
51
0
0
use factorial number system
Reversed Permutation Index
71
0
0
math
The Angles of a Triangle
89
11
2
with rectange in histogram
Spaceship Landing Strip
94
0
0
using datetime.date
Unlucky Days
103
2
1
clear
Safe Coasts
103
0
0
BFS
String Conversion
162
0
0
BFS
Radiation Search
164
0
0
sorted
Min and Max
225
4
0
Rock
5 lines
Fibonacci Spiral's End
2
0
0
get unsocial chains and with product\compress remove combinations of benches from chains
Park Benches
4
5
1
dichotomy (half-division method)
Super Root
8
10
2
combinations
Garland
10
0
0
Second
Fibonacci Spiral's End
16
2
0
6 lines
Fibonacci Spiral's End
22
0
1
First
Sort by Removing
33
2
0
recursion
Greedy Number
40
0
0
Shelter
recursion
Halloween Monsters
1
13
1
simple lifehack
Four To The Floor
4
8
0
First
Landing Site
5
5
0
1 line, clear math
The Nearest Square Number
7
11
1
First
Completely Empty
22
6
0
recursion
Delivery Drone
37
0
0
Euler path by stack
One line Drawing
77
0
0
First
Ghosts Age
116
4
0
set
Seven Segment
238
0
0
Codeship
generator
Champernowne Word
1
10
2
dice as a list
Rolling 🎲!
3
9
1
Hermit
First
Birthday Party
5
2
1
recursion
Stacking Cubes
8
3
1
sympy.expand
Simplification
8
0
0
re.sub + while
Backspace Apply
9
5
1
data.discard()
Shorter Set
13
5
1
set & hypot
Colder-Warmer
16
4
1
Fraction and match\case
Fractions Addition
19
3
1
DFS
Network Loops
20
2
1
data.difference_update()
Shorter Set
20
2
0
math + asin
Strawberry Fields
37
0
0
First
Unique Email Addresses
57
0
0
simple sum
Excel Column Number
60
0
0
First
Stock Profit
71
0
0
Second
Ore In The Desert
76
0
0
bruteforce
Break Rings
81
2
0
First
Count Consecutive Summers
122
2
1
First
The Good Radix
253
0
0
Watchtower
recursion
Stepping Stones Puzzle
7
0
0
Jarvis
Convex Hull
91
0
0
First
Funny Addition
179
4
2
First
Rotate Hole
528
0
0
Escher
First
Safe Code
18
5
0
First
Treasures
37
2
3
First
Hypercube
59
0
0
set
The Buttons
64
0
0
deck remove
Card Game
75
0
0
win position
The Stones
82
0
0
First
The Ship Teams
86
4
1
First
Keys and Locks
97
0
0
First
The Secret Room
135
0
0
First
Wild Dogs
140
0
0
First
Ground for the House
143
1
0
First
The Stone Wall
231
0
0
First
Compass, Map and Spyglass
255
0
0
Not On Map
dict + groupby
Most Wanted Letter
10
5
0
First
Length of the String
13
3
0
First
Aggregate and Count
69
0
2
