title: How to implement an efficient algorithm to search for a word in JSON?
body: <p>I am trying to implement a word game, where a user types a letter on a board to form a meaningful word and submitt it, if the typed word is present in a JSON file, the user gets a point. So I have implemented the basics of the game, but unfortunately I have found that my linear algorithm is inefficient to traverse about 400k words in the JSON file. So my question is what kind of algorithm I can write to make it efficient?
  My interface looks like this. Letters appear randomly on the board.</p>
  
  <p><a href="https://i.stack.imgur.com/B5oSR.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/B5oSR.png" alt="enter image description here"></a></p>
  
  <p>A tiny part of my JSON file look like this</p>
  
  <pre><code>{"a": 1, "aa": 1, "aaa": 1, "aah": 1, "aahed": 1, "aahing": 1, "aahs": 1, "aal": 1, "aalii": 1, "aaliis": 1, "aals": 1, "aam": 1, "aani": 1, "aardvark": 1, "aardvarks": 1, "aardwolf": 1, "aardwolves": 1, "aargh": 1, "aaron": 1, "aaronic": 1, "aaronical": 1, "aaronite": 1, "aaronitic": 1, "aarrgh": 1, "aarrghh": 1, "aaru": 1, "aas": 1, "aasvogel": 1, "aasvogels": 1, "ab": 1, "aba": 1, "ababdeh": 1, "ababua": 1, "abac": 1, "abaca": 1, "abacay": 1, "abacas": 1, "abacate": 1, "abacaxi": 1, "abaci": 1, "abacinate": 1, "abacination": 1, "abacisci": 1, "abaciscus": 1, "abacist": 1, "aback": 1, "abacli": 1, "abacot": 1, "abacterial": 1, "abactinal": 1, "abactinally": 1, "abaction": 1, "abactor": 1, "abaculi": 1, "abaculus": 1, "abacus": 1, "abacuses": 1, "abada": 1, "abaddon": 1, "abadejo": 1, "abadengo": 1, "abadia": 1, "abadite": 1, "abaff": 1, "abaft": 1, "abay": 1, "abayah": 1, "abaisance": 1, "abaised": 1, "abaiser": 1, "abaisse": 1, "abaissed": 1, "abaka": 1, "abakas": 1, "abalation": 1, "abalienate": 1, "abalienated": 1, "abalienating": 1, "abalienation": 1, "abalone": 1, "abalones": 1, "abama": 1, "abamp": 1, "abampere": 1, "abamperes": 1, "abamps": 1, "aband": 1, "abandon": 1, "abandonable": 1, "abandoned": 1, "abandonedly": 1, "abandonee": 1, "abandoner": 1, "abandoners": 1, "abandoning": 1, "abandonment": 1, "abandonments": 1, "abandons": 1, "abandum": 1, "abanet": 1, "abanga": 1, "abanic": 1, "abannition": 1, "abantes": 1, "abapical": 1, "abaptiston": 1, "abaptistum": 1, "abarambo": 1, "abaris": 1, "abarthrosis": 1, "abarticular": 1, "abarticulation": 1, "abas": 1, "abase": 1, "abased": 1, "abasedly": 1, "abasedness": 1, "abasement": 1, "abasements": 1, "abaser": 1, "abasers": 1, "abases": 1, "abasgi": 1, "abash": 1, "abashed": 1, "abashedly": 1, "abashedness": 1, "abashes": 1, "abashing": 1, "abashless": 1, "abashlessly": 1, "abashment": 1, "abashments": 1, "abasia": 1, "abasias": 1, "abasic": 1, "abasing": 1, "abasio": 1, "abask": 1, "abassi": 1, "abassin": 1, "abastard": 1, "abastardize": 1, "abastral": 1, "abatable": 1, "abatage": 1, "abate": 1, "abated": 1, "abatement": 1, "abatements": 1, "abater": 1, "abaters": 1, "abates": 1, "abatic": 1, "abating": 1, "abatis": 1, "abatised": 1, "abatises": 1, "abatjour": 1, "abatjours": 1, "abaton": 1, "abator": 1, "abators": 1, "abattage": 1, "abattis": 1, "abattised": 1, "abattises": 1, "abattoir": 1, "abattoirs": 1, "abattu": 1, "abattue": 1, "abatua": 1, "abature": 1, "abaue": 1, "abave": 1, "abaxial": 1, "abaxile": 1, "abaze": 1, "abb": 1, "abba": 1, "abbacy": 1, "abbacies": 1, "abbacomes": 1, "abbadide": 1, "abbaye": 1, "abbandono": 1, "abbas": 1, "abbasi": 1, "abbasid": 1, "abbassi": 1, "abbasside": 1, "abbate": 1, "abbatial": 1, "abbatical": 1, "abbatie": 1, "abbe": 1, "abbey": 1, "abbeys": 1, "abbeystead": 1, "abbeystede": 1, "abbes": 1, "abbess": 1, "abbesses": 1, "abbest": 1, "abbevillian": 1, "abby": 1, "abbie": 1, "abboccato": 1, "abbogada": 1, "abbot": 1, "abbotcy": 1, "abbotcies": 1, "abbotnullius": 1, "abbotric": 1, "abbots": 1, "abbotship": 1, "abbotships": 1, "abbott": 1, "abbozzo": 1, "abbr": 1, "abbrev": 1, "abbreviatable": 1, "abbreviate": 1, "abbreviated": 1, "abbreviately": 1, "abbreviates": 1, "abbreviating": 1, "abbreviation": 1, "abbreviations": 1, "abbreviator": 1, "abbreviatory": 1, "abbreviators": 1, "abbreviature": 1, "abbroachment": 1, "abc": 1, "abcess": 1, "abcissa": 1, "abcoulomb": 1, "abd": 1, "abdal": 1, "abdali": 1, "abdaria": 1, "abdat": 1, "abderian": 1, "abderite": 1, "abdest": 1, "abdicable": 1, "abdicant": 1, "abdicate": 1, "abdicated": 1, "abdicates": 1, "abdicating": 1, "abdication": 1, "abdications": 1, "abdicative": 1, "abdicator": 1, "abdiel": 1, "abditive": 1, "abditory": 1, "abdom": 1, "abdomen": 1, "abdomens": 1, "abdomina": 1, "abdominal": 1, "abdominales": 1, "abdominalia": 1, "abdominalian": 1, "abdominally": 1, "abdominals": 1, "abdominoanterior": 1, "abdominocardiac": 1, "abdominocentesis": 1, "abdominocystic": 1, "abdominogenital": 1, "abdominohysterectomy": 1, "abdominohysterotomy": 1, "abdominoposterior": 1, "abdominoscope": 1, "abdominoscopy": 1, "abdominothoracic": 1, "abdominous": 1, "abdominovaginal": 1, "abdominovesical": 1, "abduce": 1, "abduced": 1, "abducens": 1, "abducent": 1, "abducentes": 1, "abduces": 1, "abducing": 1, "abduct": 1, "abducted": 1, "abducting": 1, "abduction": 1, "abductions": 1, "abductor": 1, "abductores": 1, "abductors": 1, "abducts": 1, "abe": 1, "abeam": 1, "abear": 1, "abearance": 1, "abecedaire": 1, "abecedary": 1, "abecedaria": 1, "abecedarian": 1, "abecedarians": 1, "abecedaries": 1, "abecedarium": 1, "abecedarius": 1, "abed": 1, "abede": 1, "abedge": 1, "abegge": 1, "abey": 1, "abeyance": 1, "abeyances": 1, "abeyancy": 1, "abeyancies": 1, "abeyant": 1, "abeigh": 1, "abel": 1, "abele": 1, "abeles": 1, "abelia": 1, "abelian": 1, "abelicea": 1, "abelite": 1, "abelmoschus": 1, "abelmosk": 1, "abelmosks": 1, "abelmusk": 1, "abelonian": 1, "abeltree": 1, "abencerrages": 1, "abend": 1, "abends": 1, "abenteric": 1, "abepithymia": 1, "aberdavine": 1, "aberdeen": 1, "aberdevine": 1, "aberdonian": 1, "aberduvine": 1, "aberia": 1, "abernethy": 1, "aberr": 1, "aberrance": 1, "aberrancy": 1, "aberrancies": 1, "aberrant": 1, "aberrantly": 1, "aberrants": 1, "aberrate": 1, "aberrated": 1, "aberrating": 1, "aberration": 1, "aberrational": 1, "aberrations": 1, "aberrative": 1, "aberrator": 1, "aberrometer": 1, "aberroscope": 1, "aberuncate": 1, "aberuncator": 1, "abesse": 1, "abessive": 1, "abet": 1, "abetment": 1, "abetments": 1, "abets": 1, "abettal": 1, "abettals": 1, "abetted": 1, "abetter": 1, "abetters": 1, "abetting": 1, "abettor": 1, "abettors": 1, "abevacuation": 1, "abfarad": 1, "abfarads": 1, "abhenry": 1, "abhenries": 1, "abhenrys": 1, "abhinaya": 1, "abhiseka": 1, "abhominable": 1, "abhor": 1, "abhorred": 1, "abhorrence": 1, "abhorrences": 1, "abhorrency": 1, "abhorrent": 1, "abhorrently": 1, "abhorrer": 1, "abhorrers": 1, "abhorrible": 1, "abhorring": 1, "abhors": 1, "abhorson": 1, "aby": 1, "abib": 1, "abichite": 1, "abidal": 1, "abidance": 1, "abidances": 1, "abidden": 1, "abide": 1, "abided": 1, "abider": 1, "abiders": 1, "abides": 1, "abidi": 1, "abiding": 1, "abidingly": 1, "abidingness": 1, "abie": 1, "abye": 1, "abiegh": 1, "abience": 1, "abient": 1, "abies": 1, "abyes": 1, "abietate": 1, "abietene": 1, "abietic": 1, "abietin": 1, "abietineae": 1, "abietineous": 1, "abietinic": 1, "abietite": 1, "abiezer": 1, "abigail": 1, "abigails": 1, "abigailship": 1, "abigeat": 1, "abigei": 1, "abigeus": 1, "abying": 1, "abilao": 1, "abilene": 1, "abiliment": 1, "abilitable": 1, "ability": 1, "abilities": 1, "abilla": 1, "abilo": 1, "abime": 1, "abintestate": 1, "abiogeneses": 1, "abiogenesis": 1, "abiogenesist": 1, "abiogenetic": 1, "abiogenetical": 1, "abiogenetically": 1, "abiogeny": 1, "abiogenist": 1, "abiogenous": 1, "abiology": 1, "abiological": 1, "abiologically": 1, "abioses": 1, "abiosis": 1, "abiotic": 1, "abiotical": 1, "abiotically": 1, "abiotrophy": 1, "abiotrophic": 1, "abipon": 1, "abir": 1, "abirritant": 1, "abirritate": 1, "abirritated": 1, "abirritating": 1, "abirritation": 1, "abirritative": 1, "abys": 1, "abysm": 1, "abysmal": 1, "abysmally": 1, "abysms": 1, "abyss": 1, "abyssa": 1, "abyssal": 1, "abysses": 1, "abyssinia": 1, "abyssinian": 1, "abyssinians": 1, "abyssobenthonic": 1, "abyssolith": 1, "abyssopelagic": 1, "abyssus": 1, "abiston": 1, "abit": 1, "abitibi": 1, "abiuret": 1, "abject": 1, "abjectedness": 1, "abjection": 1, "abjections": 1, "abjective": 1, "abjectly": 1, "abjectness": 1, "abjoint": 1, "abjudge": 1, "abjudged": 1, "abjudging": 1, "abjudicate": 1, "abjudicated": 1, "abjudicating": 1, "abjudication": 1, "abjudicator": 1, "abjugate": 1, "abjunct": 1, "abjunction": 1, "abjunctive": 1, "abjuration": 1, "abjurations": 1, "abjuratory": 1, "abjure": 1, "abjured": 1, "abjurement": 1, "abjurer": 1, "abjurers": 1, "abjures": 1, "abjuring": 1, "abkar": 1, "abkari": 1, "abkary": 1, "abkhas": 1, "abkhasian": 1, "abl": 1, "ablach": 1, "ablactate": 1, "ablactated": 1, "ablactating": 1, "ablactation": 1, "ablaqueate": 1, "ablare": 1, "ablastemic": 1, "ablastin": 1, "ablastous": 1, "ablate": 1, "ablated": 1, "ablates": 1, "ablating": 1, "ablation": 1, "ablations": 1, "ablatitious": 1, "ablatival": 1, "ablative": 1, "ablatively": 1, "ablatives": 1, "ablator": 1, "ablaut": 1, "ablauts": 1, "ablaze": 1, "able": 1, "ableeze": 1, "ablegate": 1, "ablegates": 1, "ablegation": 1, "ablend": 1, "ableness": 1, "ablepharia": 1, "ablepharon": 1, "ablepharous": 1, "ablepharus": 1, "ablepsy": 1, "ablepsia": 1, "ableptical": 1, "ableptically": 1, "abler": 1, "ables": 1, "ablesse": 1, "ablest": 1, "ablet": 1, "ablewhackets": 1, "ably": 1, "ablings": 1, "ablins": 1, "ablock": 1, "abloom": 1, "ablow": 1, "ablude": 1, "abluent": 1, "abluents": 1, "ablush": 1, "ablute": 1, "abluted": 1, "ablution": 1, "ablutionary": 1, "ablutions": 1, "abluvion": 1, "abmho": 1, "abmhos": 1, "abmodality": 1, "abmodalities": 1, "abn": 1, "abnaki": 1, "abnegate": 1, "abnegated": 1, "abnegates": 1, "abnegating": 1, "abnegation": 1, "abnegations": 1, "abnegative": 1, "abnegator": 1, "abnegators": 1, "abner": 1, "abnerval": 1, "abnet": 1, "abneural": 1, "abnormal": 1, "abnormalcy": 1, "abnormalcies": 1, "abnormalise": 1, "abnormalised": 1, "abnormalising": 1, "abnormalism": 1, "abnormalist": 1, "abnormality": 1, "abnormalities": 1, "abnormalize": 1, "abnormalized": 1, "abnormalizing": 1, "abnormally": 1, "abnormalness": 1, "abnormals": 1, "abnormity": 1, "abnormities": 1, "abnormous": 1, "abnumerable": 1, "abo": 1, "aboard": 1, "aboardage": 1, "abobra": 1, "abococket": 1, "abodah": 1, "abode": 1, "aboded": 1, "abodement": 1, "abodes": 1, "abody": 1, "aboding": 1, "abogado": 1, "abogados": 1, "abohm": 1, "abohms": 1, "aboideau": 1, "aboideaus": 1, "aboideaux": 1, "aboil": 1, "aboiteau": 1, "aboiteaus": 1, "aboiteaux": 1, "abolete": 1, "abolish": 1, "abolishable": 1, "abolished": 1, "abolisher": 1, "abolishers": 1, "abolishes": 1, "abolishing": 1, "abolishment": 1, "abolishments": 1, "abolition": 1, "abolitionary": 1, "abolitionise": 1, "abolitionised": 1, "abolitionising": 1, "abolitionism": 1, "abolitionist": 1, "abolitionists": 1, "abolitionize": 1, "abolitionized": 1, "abolitionizing": 1, "abolla": 1, "abollae": 1, "aboma": 1, "abomas": 1, "abomasa": 1, "abomasal": 1, "abomasi": 1, "abomasum": 1, "abomasus": 1, "abomasusi": 1, "abominability": 1, "abominable": 1, "abominableness": 1, "abominably": 1, "abominate": 1, "abominated": 1, "abominates": 1, "abominating": 1, "abomination": 1, "abominations": 1, "abominator": 1, "abominators": 1, "abomine": 1, "abondance": 1, "abongo": 1, "abonne": 1, "abonnement": 1, "aboon": 1, "aborad": 1, "aboral": 1, "aborally": 1, "abord": 1, "aboriginal": 1, "aboriginality": 1, "aboriginally": 1, "aboriginals": 1, "aboriginary": 1, "aborigine": 1, "aborigines": 1, "aborning": 1, "aborsement": 1, "aborsive": 1, "abort": 1, "aborted": 1, "aborter": 1, "aborters": 1, "aborticide": 1, "abortient": 1, "abortifacient": 1, "abortin": 1, "aborting": 1, "abortion": 1, "abortional": 1}
  </code></pre>
  
  <p>My JS code looks like this. </p>
  
  <pre><code> document.getElementById('button').addEventListener('click', loadData);
  
      const letters = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o',
  'p','q','r','s','t','u','v','w','x','y','z'];
  
      var searched_word = '';
  
      var boxes = document.querySelectorAll('.square');
      //console.log(boxes);
  
      function clickBox() {
        boxes.forEach(function(box) {
          box.addEventListener('click', function(e) {
            e.preventDefault();
            //console.log(this.innerHTML);
            //return this.innerHTML;
            searched_word += this.innerHTML;
            document.querySelector('.input').value = searched_word;
            //console.log(searched_word);
          });
        });
        return searched_word;
      }
  
      function randomLetters(boxes) {
        for (var i = 0; i &lt; boxes.length; i++) {
          let box = boxes[i];
          let randomLetterNumber = Math.floor(Math.random() * letters.length);
          box.innerHTML = letters[randomLetterNumber].toLocaleUpperCase();
          //console.log(box);
          //console.log(randomLetterNumber);
        }
      }
  
      function loadData() {
        const xhr = new XMLHttpRequest();
        xhr.open('GET', 'words_dictionary_full.json', true);
        xhr.onload = function() {
          if (this.status === 200) {
            const words = JSON.parse(this.responseText);
            for (word in words) {
              //console.log(word);
              if (word === clickBox().toLowerCase()) {
                console.log('true');
              } else {
                console.log('false');
              }
            }
          }
        };
        xhr.send();
      }
  
      clickBox();
      randomLetters(boxes);
  </code></pre>