All Questions
7 questions
7votes
2answers
1kviews
Letter Combinations of a phone number using a Dictionary
Problem statement (online source) Given a digit string, return all possible letter combinations that the number could represent. A mapping of digit to letters (just like on the telephone ...
- 103
5votes
2answers
1kviews
Finding all possible letter combinations from an inputted phone number
Prompt: Given a string containing digits from 2-9 inclusive, return all possible letter combinations that the number could represent. A mapping of digit to letters (just like on the telephone ...
- 175
1vote
1answer
126views
Count all possible attendance records with length n, which will be regarded as rewardable
Given a positive integer n, return the number of all possible attendance records with length n, which will be regarded as rewardable. The answer may be very large, return it after \$\mod 10^9 + 7\$. ...
- 261
4votes
1answer
408views
Counting ways to fit bottles in crates
I'm calculating how many possibilities there are to fit \$n\$ identical bottles inside \$k\$ crates of various capacities. n = Number of bottles k = Number of crates K = List of the number of bottles ...
10votes
2answers
449views
You need to diversify your strings
Challenge: Write a program which prints all the permutations of a string in alphabetical order. Specifications: Your program should accept a file as its first argument. The file contains input ...
- 9,839
4votes
4answers
9kviews
Staircase problem solved using recursion
Problem Question taken from here. I want to go up a flight of stairs that has n steps. I can either take 1 or 2 steps each time. How many different ways can I go up this flight of stairs? Write a ...
- 3,401
8votes
2answers
4kviews
Consecutive Primes challenge at CodeEval.com and memory allocation issue
I finally solved this challenge with using recursion and figured out why the automatic scorer wasn't passing my previous solutions. I was using NSMutableArray to ...
- 683
