Coding interview problems

Free. No login required. Python technical interview question: Two Sum

Given a collection of intervals, merge any overlapping intervals.

reverse a string interview question

Find the longest common prefix string amongst an array of strings.

Palindrome String: Free. No login required. Python technical interview question

Given a Roman numeral, convert it to an integer. Input is guaranteed to be within the range from 1 to 3999.

Write a function to generate all possible combinations of letters that can be formed from a given string of digits representing a phone number.

valid parentheses coding question

Learn how to find the index of the first occurrence of a substring in a string in this coding interview problem.

Find the length of the last word in a given string.

given number n return matrix n by n with numbers in spiral order