All Questions
Tagged with programming-challenge performance
629 questions
59
votes
9
answers
14k
views
Project Euler problem 1 in Python - Multiples of 3 and 5
I'd like suggestions for optimizing this brute force solution to problem 1. The algorithm currently checks every integer between 3 and 1000. I'd like to cut as many unnecessary calls to ...
- 699
33
votes
7
answers
6k
views
Project Euler #7 10001st prime
I decided to start working on the Euler project exercises. I'm doing fine for now but the seventh problem is running quite slow and I can't think of anything to make it work faster. It takes around ...
- 8,508
32
votes
8
answers
5k
views
Project Euler Problem 45
As a self-teaching Python beginner for almost 4 months, I have mostly been doing online challenges including Project Euler problems.
Problem 45 asks:
Triangle, pentagonal, and hexagonal numbers ...
- 475
32
votes
6
answers
3k
views
Aliens at the train
I solved this problem on SPOJ:
The aliens have arrived to Earth and everything is in harmony, the two
races can live together. However, one specific Female Alien does not
want to see humans on ...
30
votes
3
answers
27k
views
Perm-Missing-Elem: 100% functional score, but only 60% performance
I cannot figure out why I didn't get 100% success from the Codility's Perm-Missing-Element test even I solve with \$O(n)\$. I will appreciate any advice/answers.
You can see the problem, my code, and ...
- 505
30
votes
6
answers
4k
views
DailyProgrammer 284: Wandering Fingers
Description
Software like Swype and SwiftKey lets smartphone users enter text by dragging their finger over the on-screen keyboard, rather than tapping on each letter.
You'll be given ...
- 403
26
votes
2
answers
6k
views
Printing 1,000,000 numbers in 1 sec. in Python
Here's a fairly simple task from CSES Problem Set - Permutations 1070 that reads:
A permutation of integers 1,2, …, n is called beautiful if there are no adjacent elements whose difference is 1.
...
- 507
25
votes
2
answers
2k
views
Speed up solution to Project Euler problem 75
I wrote this code for Project Euler problem 75, which asks how many integers ≤ 1500000 exist, where the integer is a perimeter length that can be divided into three integer-length sides of a right ...
- 251
25
votes
5
answers
2k
views
Count distinct primes, discarding palindromes, in under 2 seconds
Problem Statement
Generate as many distinct primes P such that reverse (P) is also prime
and is not equal to P.
Output:
Print per line one integer( ≤ 1015 ). Don't print more than
106 ...
- 505
24
votes
12
answers
4k
views
Project Euler 8: Maximum product of 13 adjacent digits
Problem 8 on Project Euler which asks
Find the thirteen adjacent digits in the 1000-digit number that have the greatest product. What is the product?
This is my solution in Visual C#.
...
- 585
23
votes
5
answers
18k
views
Finding the 10001st prime
I'm solving Project Euler problem 7, which says:
By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can see that the 6th prime is 13. What is the 10001st prime number?
Here's the ...
- 333
20
votes
5
answers
3k
views
Print the N longest lines in a file
I have implemented the "Find the N longest lines in a file" problem from CodeEval quoted below.
I got a full 100 score and 182ms execution time of their data set on the site so I consider the code ...
- 16.6k
19
votes
6
answers
7k
views
Determining if the kangaroos will land in the same position
Problem
There are two kangaroos on an x-axis ready to jump in the positive
direction (i.e, toward positive infinity). The first kangaroo starts
at location x1 and moves at a rate of v1 meters ...
- 365
19
votes
2
answers
2k
views
"ACM ICPC Team" challenge on Hackerrank... Easy?
This challenge took me awhile to figure out, and it's characterized as "easy," so I'm sorta wondering what I missed.
Problem Statement
You are given a list of N people who are attending ACM-...
- 409
17
votes
4
answers
2k
views
Duplicate like a weapon, arrays like heaven
Challenge:
Find the duplicated entry.
Specifications:
Your program should accept as its first argument a path to a filename.
Each line in this file is one test case.
Each line begins ...
- 9,839
16
votes
6
answers
4k
views
Sherlock and The Beast
This is my solution to this question from Hackerrank.
Given N (<= 100000), find the largest N-digit number such that:
The number has only 3 and 5 as its digits.
Number of times 3 ...
- 543
16
votes
4
answers
3k
views
Sieve of Sundaram for Project Euler 7: Python implementation slower than C++ and R
A friend of mine recently started learning R, and she complained to me that R is very slow. She was working on Project Euler Problem 7, which asks for the value of the 10001st prime number. For ...
- 591
13
votes
5
answers
22k
views
Smallest Multiple
I just recently learned about Project Euler and have started doing the problems on there. I cleared problem 1 and 2, had no idea how to do 3 and 4, and started to do 5. I've seen the post regarding ...
- 233
13
votes
3
answers
4k
views
Codewars: Reduce strings to one character
I am trying to solve a puzzle in a performant way. This is the puzzle.
Simply explained: you have a String and you must reduce it to one character with the given rules. This is the solution to the ...
- 461
13
votes
3
answers
8k
views
Find total number of phone numbers formed by the movement of Knight and Bishop on keypad
I recently took a test on HackerRank, and submitted my answer for the following question. I passed all the test cases but company told me that the answer is not efficient, and they are not moving ...
- 623
13
votes
4
answers
660
views
Finding the largest of a series of numbers being XORed
I'm working on solving a problem involving finding the largest of a series of numbers being XORed.
This is the actual problem:
Xorq has invented an encryption algorithm which uses bitwise XOR
...
- 337
13
votes
3
answers
5k
views
The Beauty and the Strings
This originally appeared in Facebook's hacker cup 2013. Solving it was fun, though I find myself looping through similar data quite often.
Challenge:
Print the maximum beauty of strings.
...
- 9,839
12
votes
3
answers
6k
views
Project Euler Problem 12 - triangle number with 500 divisors
I've just done Problem 12 of Project Euler:
What is the value of the first triangle number to have over five hundred divisors?
The \$N\$'th triangle number is the sum of all natural numbers ...
12
votes
3
answers
16k
views
Project Euler Problem 12 in Python
I'm trying to do Project Euler Problem 12, which reads as:
The sequence of triangle numbers is generated by adding the natural
numbers. So the 7th triangle number would be 1 + 2 + 3 + 4 + 5 + 6 + ...
- 223
12
votes
2
answers
599
views
Cows with walkie-talkies (USACO Silver Prob. #3; December '16 )
The official problem description is here, which in my opinion is unclear and quite long. Below is my description. I recommend you still read the official description, it has details such as input and ...
- 349
12
votes
2
answers
5k
views
Generating 'Decent' numbers
While solving a problem from HackerRank, though it's an easy one, I wrote this big program. Not sure if recursion is applicable and hold good but to me it looked like it isn't. However when I run the ...
- 235
12
votes
2
answers
5k
views
Contest code for a maze problem
I would like to ask your comments on my contest code for the following problem:
We're going to have a slightly more logical puzzle today. We're going to write a program that will find a path through ...
- 223
11
votes
3
answers
6k
views
Algorithm for competing cells of 0s and 1s
I'm working on a practice algorithm problem, stated as follows:
There are eight houses represented as cells. Each day, the houses compete with adjacent ones. 1 represents an "active" house and 0 ...
- 213
11
votes
4
answers
27k
views
Find the binary gap of a number N
For example, number 9 has binary representation 1001 and contains a binary gap of length 2. The number 529 has binary representation 1000010001 and contains two binary gaps: one of length 4 and one of ...
- 201
11
votes
3
answers
1k
views
Optimizing "Herd Sums" problem using dynamic programming
I'm trying to solve a practice problem and all is well except for the last 2 inputs my solution is too slow. Just one loop is slowing it down I think.
Herd Sums
Execution Time Limit: 2 seconds
...
- 213
11
votes
2
answers
172
views
What a crooked way to compute the next straight string (advent of code 11)
This year I have been participating in the Advent of Code series of challenges, and it just so happened that I'd be doing them in Javascript. Not my usual weapon of choice, but I do have some ...
- 1,228
10
votes
9
answers
13k
views
Project Euler #5 - Lowest Multiple of 1 through 20
I was trying to solve problem 5 of Project Euler, and this was I needed to do:
2520 is the smallest number that can be divided by each of the numbers
from 1 to 10 without any remainder.
What ...
- 203
10
votes
2
answers
3k
views
Project Euler #7 10001st prime in C++
By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can
see that the 6th prime is 13.
What is the 10 001st prime number?
How can I optimize this code?
...
- 2,451
10
votes
3
answers
1k
views
Solution to Project Euler Problem #37 in C++: Truncatable Primes
I was recently looking at some of my old Project Euler solutions, and saw that my implementation for Problem 37 could be improved drastically.
The problem reads as follows:
The number 3797 has an ...
- 1,098
10
votes
3
answers
537
views
How can I make my solution for Chef and Digits run faster?
Problem Statement
Given \$n\$ digits and \$m\$ indices \$x\$ from \$1. \ldots,n\$, calculate the
difference \$b_y = a_x - a_y\$ for all indices \$y \; (y < x)\$. Then, calculate \$B1\$,
the ...
- 505
10
votes
2
answers
4k
views
Finding the Mth to last Element
Challenge:
Write a program which determines the Mth to last element in a list.
Specifications:
The first argument is a path to a file.
The file contains series of space delimited characters
...
- 9,839
10
votes
1
answer
2k
views
Google Kickstart Round A 2019 - Training
Problem: Training
As the football coach at your local school, you have been tasked with
picking a team of exactly P students to represent your school. There
are N students for you to pick ...
- 261
10
votes
2
answers
624
views
The finest integers are palindromes
Challenge:
Reverse the digits of a number and add it to the original
until the number is a palindrome
Specifications:
Your program should accept as its first argument a path to a filename.
...
- 9,839
10
votes
3
answers
491
views
Selecting kids for a Christmas play with similar heights
I am doing this problem on SPOJ:
My kid's kindergarten class is putting up a Christmas play. (I hope he gets the lead role.) The kids are all excited, but the teacher has a lot of work. She has ...
- 155
10
votes
1
answer
305
views
Tweets per second, using linked list
This is a TalentBuddy Challenge
Your task is to
write a function that prints to the standard output (stdout) the highest number of tweets recorded between each second in the array and the past <...
- 4,278
9
votes
4
answers
2k
views
Leetcode : First Missing Positive
I was trying out leetcode's first missing positive.
As per the challenge's description:
Given an unsorted integer array nums, return the smallest missing
positive integer.
You must implement an ...
- 341
9
votes
3
answers
2k
views
LeetCode 1108: Defanging an IP Address
I'm posting two solutions for LeetCode's "Defanging an IP Address". If you'd like to review, please do. Thank you!
Problem
Given a valid (IPv4) IP address, return a defanged version of that ...
- 3,542
9
votes
2
answers
11k
views
Optimizing solution for Project Euler Problem #23 (non-abundant sums)
Project Euler Problem 23 asks:
A perfect number is a number for which the sum of its proper divisors
is exactly equal to the number. For example, the sum of the proper
divisors of 28 would be 1 ...
9
votes
5
answers
718
views
Ten thousand and first prime checker takes a very long time
I am attempting problem 7 on Project Euler. I have come up with this solution which works fine for finding smaller nth prime numbers, but really lags when it comes to higher nth prime numbers. I am ...
- 541
9
votes
3
answers
626
views
CSES standard solution for range query problem giving TLE
Problem statement is from CSES
This is a standard question where we are given a list of numbers and a number of queries. For each query, you have to give the sum of numbers in the given range.
My ...
- 193
9
votes
3
answers
11k
views
Project Euler #9 - Pythagorean triplets
This code works, and I'm trying to figure out if there's a better way to optimize it. As you can see, I've cut down drastically on time just by using numbers that work for ...
- 285
9
votes
1
answer
2k
views
Codility MaxCounters peformance in Python capping out at 77% performance
My problem is quite similar to the question found here, except I am attempting to answer the question in Python.
Given an array of N counters, all initialized to 0, and an array ...
9
votes
1
answer
620
views
Horridly Inefficient Project Euler #14 in Python - Collatz Sequences
I created this solution a while ago, and have been going back over my problems to try to make them all more efficient. I have been stuck on this one, and have tried a few different ideas. So far, my ...
- 285
9
votes
2
answers
4k
views
Python 3 two-sum performance
I just submitted a Python solution to the 'Two Sum' problem on LeetCode.
The Problem
Given an array of integers, return indices of the two numbers such
that they add up to a specific target.
...
9
votes
2
answers
275
views
Tail implementation using a dynamic queue library
As per K & R exercise 5-13
Write the program tail, which prints the last n lines of its input. By default, n is 10, say, but it can be changed by an optional argument, so that
...
- 1,378