Keskustelu: Koodit: JavaScript: Sanajahti / wordz ratkoja

const fs = require('fs');

// Game board
const board = [
  'srsp',
  'räet',
  'möth',
  'adlä'
];

// Load dictionary
const finnishDictionary = fs.readFileSync('finnishDictionary.txt', { encoding:'utf8' })
    .split('\n')
    .filter(word => word.length > 2); // include only words that are atleast 3 letters long

const findStringsThatCanBeFormedFromAnotherString = (stringArray, givenString) => {
  const charCounts = new Array(215).fill(0);
  for (let i = givenString.length - 1; i >= 0; i--) {
      charCounts[givenString[i].toUpperCase().charCodeAt(0)]++;
  }

  return stringArray.filter(str => {
    const strCharCounts = new Array(215).fill(0);
    for (let i = str.length - 1; i >= 0; i--) strCharCounts[str[i].toUpperCase().charCodeAt(0)]++;
    for (let i = 65; i < 91; i++) return charCounts[i] >= strCharCounts[i]; // A-Z
    return charCounts[196] >= strCharCounts[196] || charCounts[214] >= strCharCounts[214]; // Ä&Ö
  });
};

const wordzDFS = (boardData, words) => {
  const filteredWords = findStringsThatCanBeFormedFromAnotherString(words, boardData.join(''));
  const wordsFound = new Set();

  filteredWords.map(n => n.toUpperCase()).forEach(wordToFind => {
    const visitedSlots = new Array(4);
    for (let i = 0; i < 4; i++) {
      visitedSlots[i] = new Array(4).fill(0);
    }

    const wordBuilder = [];
    let isWordBuiltSuccesfully = false;

    const dfs = (y, x) => {
      if (
        y < 0 || y > 3 || x < 0 || x > 3 || // outside of board?
        visitedSlots[y][x] || isWordBuiltSuccesfully || // slot already visited or word already found?
        wordToFind[wordBuilder.length] !== boardData[y][x].toUpperCase() // is character in this slot correct?
      ) return;

      visitedSlots[y][x] = 1;
      wordBuilder.push(boardData[y][x].toUpperCase());

      if (wordBuilder.length === wordToFind.length) {
        if (wordBuilder.join('') === wordToFind) {
          wordsFound.add(wordToFind);
          isWordBuiltSuccesfully = true;
        }

        return;
      }

      for (let i = -1; i < 2; i++) {
        for (let j = -1; j < 2; j++) {
          if (i === 0 && j === 0) continue;
          dfs(y+i,x+j);
        }
      }

      wordBuilder.pop();
      visitedSlots[y][x] = 0;
    }

    for (let i = 0; i < 4; i++) {
      for (let j = 0; j < 4; j++) {
        // if slot has first character of word then start dfs
        if (boardData[i][j].toUpperCase() === wordToFind[0]) dfs(i,j);
      }
    }
  });

  return Array.from(wordsFound).sort((a, b) => b.length - a.length);
};

console.log(wordzDFS(board, finnishDictionary).join('\n'));