index.txt

/*
var fs = require('fs');

var distinct = array => array.filter((value,index,that) => that.indexOf(value) == index);

fs.readFile('dict.txt', 'utf8', (err,data) => {
    var dictionary = data.split(/[:.,\s]+[-=]+|[=-]+|[.:]+|[{}]+|[\r]+|[\n]+|[\r\n]+|[\s\n]+|[\n\s]+|[()]+/)
                         .filter(x => x.trim()!=="")
                         .filter(x => !isFinite(x) );
    dictionary = dictionary.map(x => x.toLowerCase().replace(/[,.'"?!]/g,''));
    dictionary = distinct(dictionary);


    //dictionary = dictionary.filter(term => ['.','',',',':',] .indexOf(term.trim()) == -1);
    var x = 1;
});
*/

Array.prototype.contains = (term) => this.indexOf(term) != -1;

var dictionary = ['which','is','the','basis','theory','of'];

var str = "|wh|  |is|th| b| o|as|is|eo|  |ry|  |f |ic| t|, |  |he|h |";
var input2 = str.split('|').filter(x => x!='' && x != '  ');

var result = [];
var R = "";
var someDictWordStartsWithR = false;
do {
    // i am removing the first element of input2 at the same time that i am it putting into R
    // but i am doing this only if the word is not fully complete (which means that the some word of the dictionary starts with R)
    if(!someDictWordStartsWithR) {
        R = input2.splice(0,1)[0];
    }

    var i = 0;
    while(i < input2.length && input2.length > 0) {
        var possibleWord = R.concat(input2[i]).trim();
        // first of all, verify if the actual R is a valid term in the dictionary
        if(dictionary.indexOf(R.toLowerCase()) != -1) {
            result.push(R);
            someDictWordStartsWithR = false;
            break;
        } else if(dictionary.indexOf(possibleWord.toLowerCase()) != -1) {
               //if(dictionary.contains()) {
            // possible word is actually a word
            // here i'm removing this term of the input2 array
            input2.splice(i,1);
            //add this word to the result
            result.push(possibleWord);
            someDictWordStartsWithR = false;
            break;
        } else if( dictionary.some(t => t.startsWith(possibleWord.toLowerCase())) ) {
            // it means that some word of the dictionary starts with 'possibleWord'. I will continue trying to find the full word
            R = possibleWord;
            someDictWordStartsWithR = true;
            input2.splice(i,1);
            break;
        } else {
            someDictWordStartsWithR = false;
            // if it's got here, it means no word starts with possibleWord nor possibleWord is a full word in the dictionary
            // here i will add nothing the final result, as possibleWord is not valid.
            // i will not delete anything from input2 because i already did it in the first place 
        }
        // this code will run until the array is empty, which means that I tried to create all the existing words possible in  the dictionary.
        // the code is not complete, it will only try and match the valid words with the dictionary (it doesnt include special characters like ",.' etc)
        i++;
    }

} while(input2.length > 0);
if(dictionary.indexOf(R.toLowerCase()) != -1) { result.push(R); }

process.exit();