This is our solution and implementation to problem #54 on Project Euler.
Our code is written in TypeScript, a language which is built on-top of JavaScript and transpiles to it. We've included the problem statement, our code (which is commented for greater clarity), our video which outlines our analysis and implementation approach, and the solution + how long it took to calculate it.
Note: the code and contents here might be slightly different than what is in the video. We've made some improvements to some of the code since recording.
If you would like to view the original problem and solve it, please visit: Poker Hands on Project Euler. If you're having trouble solving this problem, or are just curious to see how others have solved it, feel free to take a look, but please put solid effort into solving this before viewing the actual solution to the problem.
Problem Statement
In the card game poker, a hand consists of five cards and are ranked, from lowest to highest, in the following way:
- High Card: Highest value card.
- One Pair: Two cards of the same value.
- Two Pairs: Two different pairs.
- Three of a Kind: Three cards of the same value.
- Straight: All cards are consecutive values.
- Flush: All cards of the same suit.
- Full House: Three of a kind and a pair.
- Four of a Kind: Four cards of the same value.
- Straight Flush: All cards are consecutive values of same suit.
- Royal Flush: Ten, Jack, Queen, King, Ace, in same suit.
The cards are valued in the order:
2, 3, 4, 5, 6, 7, 8, 9, 10, Jack, Queen, King, Ace.
If two players have the same ranked hands then the rank made up of the highest value wins; for example, a pair of eights beats a pair of fives (see example 1 below). But if two ranks tie, for example, both players have a pair of queens, then highest cards in each hand are compared (see example 4 below); if the highest cards tie then the next highest cards are compared, and so on.
Consider the following five hands dealt to two players:
Hand | Player 1 | Player 2 | Winner | |||
1 | 5H 5C 6S 7S KD Pair of Fives | 2C 3S 8S 8D TD Pair of Eights | Player 2 | |||
2 | 5D 8C 9S JS AC Highest card Ace | 2C 5C 7D 8S QH Highest card Queen | Player 1 | |||
3 | 2D 9C AS AH AC Three Aces | 3D 6D 7D TD QD Flush with Diamonds | Player 2 | |||
4 | 4D 6S 9H QH QC Pair of Queens Highest card Nine | 3D 6D 7H QD QS Pair of Queens Highest card Seven | Player 1 | |||
5 | 2H 2D 4C 4D 4S Full House With Three Fours | 3C 3D 3S 9S 9D Full House with Three Threes | Player 1 |
The file, poker.txt, contains one-thousand random hands dealt to two players. Each line of the file contains ten cards (separated by a single space): the first five are Player 1's cards and the last five are Player 2's cards. You can assume that all hands are valid (no invalid characters or repeated cards), each player's hand is in no specific order, and in each hand there is a clear winner.
How many hands does Player 1 win?
Our Solution
Our solution is given in the TypeScript code below:
Results
This implementation found the solution in 20ms.
If you would like to view the answer, click below to reveal. Please consider reviewing the implementation and trying to code your own solution before viewing the answer.
View Answer
The answer is 376.
All of our solutions are hosted on GitHub. The code on this page was pulled from the repo and the solution and execution time were calculated based on that code.