diff --git a/deno.lock b/deno.lock
index 600baf8..e78ddd4 100644
--- a/deno.lock
+++ b/deno.lock
@@ -6,6 +6,7 @@
     "https://unpkg.com/pure-rand/lib/esm/pure-rand.js": "https://unpkg.com/pure-rand@6.0.4/lib/esm/pure-rand.js"
   },
   "remote": {
+    "https://cdn.jsdelivr.net/npm/highlight.js@11.9.0": "91a9625e96503cd01729ec392b4dfb0a33d6062395c1907041344bd7706ac099",
     "https://deno.land/std@0.200.0/_util/os.ts": "d932f56d41e4f6a6093d56044e29ce637f8dcc43c5a90af43504a889cf1775e3",
     "https://deno.land/std@0.200.0/assert/assert.ts": "9a97dad6d98c238938e7540736b826440ad8c1c1e54430ca4c4e623e585607ee",
     "https://deno.land/std@0.200.0/assert/assertion_error.ts": "4d0bde9b374dfbcbe8ac23f54f567b77024fb67dbb1906a852d67fe050d42f56",
@@ -185,13 +186,19 @@
     "https://denopkg.com/chiefbiiko/sha1@master/deps.ts": "434b70f37ed145ca5259353c96fdee1e7d1cd8c6a32baad9dce2aedc79d0a3bc",
     "https://denopkg.com/chiefbiiko/sha1@master/mod.ts": "146a101c9776cc9c807053c93f23e4b321ade5251f65745df418f4a75d5fd27b",
     "https://denopkg.com/chiefbiiko/std-encoding@v1.1.1/mod.ts": "e61017da4cef146863d614a961b4e61f1df14b72c906092bd02161f913e76522",
+    "https://esm.sh/highlight.js@11.9.0": "fedce3b9e0d80a1302f7880a5db7527b00fb565777abe6350769883790465c65",
+    "https://esm.sh/highlight.js@11.9.0/es/languages/javascript.js": "28afc23607edc404bc69093b2f1eb82dbae810e3ef6bf1357c3e90b5bb5c6fea",
     "https://esm.sh/preact-render-to-string@5.1.19?deps=preact@10.5.15": "fba6961b9688151eeccc5425e05740009c3e7abee863615e626fb13e1d17e87a",
     "https://esm.sh/preact@10.19.2": "41f31ba8eecf666f08289f2205f57c45f74baba5be815a55c15c4cc61086143c",
     "https://esm.sh/preact@10.19.2/jsx-runtime": "2a4111d9aa667a3e3776ffd9082d00d63f6960c038d01620d79f80645ecc049d",
     "https://esm.sh/stable/preact@10.19.2/denonext/jsx-runtime.js": "f196c14042fc6019f3fed31eec7cfedea4669d0926858939380a5f54bd503798",
     "https://esm.sh/stable/preact@10.19.2/denonext/preact.mjs": "dc999b6432dc04d74ad7b692a8801f346294d815266dff915d0f222c120fd0b0",
     "https://esm.sh/stable/preact@10.5.15/denonext/preact.mjs": "4e6645aa945a53e44eaa4d882f9f9b4e76c992875fad9ef5791784474a71a116",
+    "https://esm.sh/v135/highlight.js@11.9.0/denonext/es/languages/javascript.js": "e6dbfe6f4e73f1ea4b346b20336e48a710be4aa516c0baad2b68721ce5fd3a7c",
+    "https://esm.sh/v135/highlight.js@11.9.0/denonext/highlight.mjs": "a6c1ad8d57cb7bff25c3e0084d9312631fa6e24cd7da5a9565314410897af271",
+    "https://esm.sh/v135/highlight.js@11.9.0/denonext/lib/core.js": "8653667a14004953b2fcbf10be691096e9f699741b23e5a858cb1e4b09f9e3b3",
     "https://esm.sh/v135/preact-render-to-string@5.1.19/X-ZC9wcmVhY3RAMTAuNS4xNQ/denonext/preact-render-to-string.mjs": "3ce1bda513633d15cd313e97ab7eacba9bd50eb4dc95e41861056c6bae1bfac8",
+    "https://unpkg.com/@highlightjs/cdn-assets@11.9.0/highlight.min.js": "837a6fa5b0c736b52bbde2b2b6190f305da3fc9ed41681db5321507057b5c846",
     "https://unpkg.com/pure-rand@6.0.4/lib/esm/distribution/UniformArrayIntDistribution.js": "121a5017f80ac3c36359877407f6f9d16cc8d28fb88e21990d1ecba6a6ad6a90",
     "https://unpkg.com/pure-rand@6.0.4/lib/esm/distribution/UniformBigIntDistribution.js": "1fafebba70f83e619d852964506bbb259e26618238b087bf7cab203b9848bf71",
     "https://unpkg.com/pure-rand@6.0.4/lib/esm/distribution/UniformIntDistribution.js": "fb21df31e3395ed0f38194ec5e99bcba6c89be02acd2d7cc07145b665d997e78",
diff --git a/public/index.html b/public/index.html
index 8108497..ec66992 100644
--- a/public/index.html
+++ b/public/index.html
@@ -6,6 +6,9 @@
     <meta http-equiv="X-UA-Compatible" content="ie=edge">
     <title>JS Reading App</title>
     <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bulma@0.9.4/css/bulma.min.css">
+    <link rel="stylesheet" href="https://cdn.jsdelivr.net/gh/highlightjs/cdn-release@11.9.0/build/styles/default.min.css">
+    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.9.0/styles/atom-one-light.min.css">
+
     <script src="https://unpkg.com/htmx.org@1.9.9"></script>
   </head>
   <body>
@@ -25,12 +28,22 @@
     </div>
 
     <script>
-        function getDefaultIndex(){
-            if(document.location.hash.length > 1){
-                return document.location.hash.substr(1)
+
+        function getIndexFromHash(){
+            if(document.location.hash.length < 2){
+                return null;
             }
-            return localStorage.getItem("defaultIndex") || '0'; 
+            const ret = document.location.hash.substr(1)
+            if(isNaN(ret)){
+                return ret;
+            }
+            return parseInt(ret) - 1;
         }
+        
+        function getDefaultIndex(){
+            return getIndexFromHash() || localStorage.getItem("defaultIndex") || '0'; 
+        }
+
         document.body.addEventListener('htmx:configRequest', function(evt) {
             evt.detail.headers.session = localStorage.getItem("seed"); 
             evt.detail.path = evt.detail.path.replace(":seed", localStorage.getItem("seed"));
@@ -46,7 +59,7 @@
             if(isNaN(evt.detail.value)){
                 return;
             }
-            document.location.hash = evt.detail.value
+            document.location.hash = parseInt(evt.detail.value) + 1;
             localStorage.setItem("defaultIndex", evt.detail.value);
         });
 
diff --git a/src/questions.js b/src/questions.js
index 08306b4..25077f8 100644
--- a/src/questions.js
+++ b/src/questions.js
@@ -6,7 +6,21 @@ function basicFrenchQuestion(argumentValue){
 }
 
 function basicQuestionValidator(expected){
-    return (answer) => answer.toString() === expected.toString();
+    const cannonicalString = (v) => {
+        if(v === null){
+            return 'null';
+        }
+        if(v === undefined){
+            return 'undefined'
+        }
+        return v.toString()
+
+    }
+
+    return (answer) => {
+        return cannonicalString(answer) === cannonicalString(expected);
+    }
+
 }
 
 function basicQuestionMetaData(question){
@@ -211,3 +225,18 @@ export function question015(x){
 question015.questions = [-4, 2, 7].map(basicQuestionMetaData(question015))
 
 
+export function question016(id){
+    const people = [{id: 12, name: "bob"}, 
+                    {id: 34, name: "alice"}, 
+                    {id: 56, name: "cedric"},
+                    {id: 6, name: "david"}, ]
+    for(const person of people){
+        if (person.id === id){
+            return person;
+        }
+    }
+}
+
+question016.questions = [12, 56, 7].map(basicQuestionMetaData(question016))
+
+
diff --git a/src/server.tsx b/src/server.tsx
index 0a6e565..143e734 100644
--- a/src/server.tsx
+++ b/src/server.tsx
@@ -5,6 +5,9 @@ import { renderToString } from "https://esm.sh/preact-render-to-string@5.1.19?de
 import * as prand from 'https://unpkg.com/pure-rand/lib/esm/pure-rand.js';
 import {QuestionSource, QuestionMeta} from './shared.ts';
 
+import highlightJs from "https://esm.sh/highlight.js@11.9.0"
+import highlightJsJavascript from "https://esm.sh/highlight.js@11.9.0/es/languages/javascript.js"
+highlightJs.registerLanguage('javascript', highlightJsJavascript);
 
 type Question = [QuestionSource, QuestionMeta];
 
@@ -14,7 +17,7 @@ type QuestionURLS = {
     answerQuestionUrl: string
 };
 
-const questions: Question = Object.values(rawQuestions).flatMap(s => s.questions.map( q => [s, q]));
+const questions: Question[] = Object.values(rawQuestions).flatMap(s => s.questions.map( (q, idx) => [s as QuestionSource, q as QuestionMeta]));
 
 const apiRouter = new Router();
 const loginRouter = new Router();
@@ -28,33 +31,43 @@ function hashString(str: string): number {
       hash |= 0; // Convert to 32bit integer
     }
     return hash;
-  }
+}
   
   
-  function randomPermutation(seed: number, n: number): number[] {
-      const rand = prand.mersenne(seed)
-      const base = [...Array(n).keys()];
-      for(let i = 0; i < (n -1); i++){
-         const j = prand.unsafeUniformIntDistribution(i, n-1, rand);
-         const tmp = base[i];
-         base[i] = base[j];
-         base[j] = tmp;
-      }
-      return base;
-  }
-
-
-function  getRandomQuestion<T>(seed: string, index: number, questions: Question[]): Question {
-    const numberSeed = hashString(seed);
-    const permutations = randomPermutation(numberSeed, questions.length)
-    return questions[permutations[index]];
-
+function randomPermutation(seed: number, n: number): number[] {
+    const rand = prand.mersenne(seed)
+    const base = [...Array(n).keys()];
+    for(let i = 0; i < (n -1); i++){
+        const j = prand.unsafeUniformIntDistribution(i, n-1, rand);
+        const tmp = base[i];
+        base[i] = base[j];
+        base[j] = tmp;
+    }
+    return base;
 }
 
-function getQuestionPage(question: Question, urls: QuestionURLS){
+function isSecretSeed(seed: string): boolean{
+    return seed === 'cannonical';
+}
+  
+
+function  getRandomQuestion<T>(seed: string, index: number, questions: Question[]): Question {
+    if(isSecretSeed(seed)){
+        return questions[index] ;
+    }
+    const numberSeed = hashString(seed);
+    const permutations = randomPermutation(numberSeed, questions.length)
+    return [... questions[permutations[index]]];
+}
+
+function getQuestionPage(question: Question, urls: QuestionURLS, questionIndex: number){
+    const source = highlightJs.highlight(question[0].toString(), {language: 'javascript'}).value;
     return (<div>
-        <pre> { question[0].toString() }</pre>
-        <div class="content mt-2 mb-2">
+        <div style="text-align:center">
+            {questionIndex + 1}/{ questions.length }
+        </div>
+        <pre> <code dangerouslySetInnerHTML={{__html: source}}></code></pre>
+        <div class="content mt-2 mb-2" >
             { question[1].question_fr }
         </div>
 
@@ -129,17 +142,26 @@ function processValidAnswer(ctx, answer: string): void {
     ctx.response.body = renderToString(getValidAnswerMessage());
 }
 
+function getQuestionIndex(ctx){
+    const index = Number.parseInt(ctx.params.idx??"0");
+    return index % questions.length;
+}
+
+function getNextQuestionIndex(ctx){
+    return (getQuestionIndex(ctx) + 1) % questions.length
+}
 
 function getQuestion(ctx): Question{
     const seed = ctx.params.seed;
-    const index = Number.parseInt(ctx.params.idx??"0");
+    const index = getQuestionIndex(ctx);
     return getRandomQuestion(seed, index, questions);
 }
 
 function getUrls(ctx): QuestionURLS{
     const seed = ctx.params.seed;
-    const index = Number.parseInt(ctx.params.idx??"0");
-    const nextQuestionUrl = `/api/v1/random-questions/${seed}/${index + 1}`;
+    const index = getQuestionIndex(ctx);
+    const nextQuestionIndex = getNextQuestionIndex(ctx);
+    const nextQuestionUrl = `/api/v1/random-questions/${seed}/${nextQuestionIndex}`;
     const validationUrl = `/api/v1/random-questions/${seed}/${index}/validate`;
     const answerQuestionUrl = `/api/v1/random-questions/${seed}/${index}/answer`
     return {nextQuestionUrl, validationUrl, answerQuestionUrl};
@@ -201,12 +223,18 @@ apiRouter.get("/api/v1/random-questions/:seed/:idx/answer", (ctx)=> {
 apiRouter.get("/api/v1/random-questions/:seed/:idx", (ctx)=> {
     const q = getQuestion(ctx);
     const urls = getUrls(ctx);
-    
-    ctx.response.body = renderToString(getQuestionPage(q, urls));
+    const questionIndex =  getQuestionIndex(ctx);
+
+    ctx.response.body = renderToString(getQuestionPage(q, urls, questionIndex));
     ctx.response.headers.append("HX-Trigger", JSON.stringify({'set-question-id': ctx.params.idx}));
 });
 
 
+loginRouter.get("/toto", (ctx)=> {
+    ctx.response.body = highlightJs.highlight('function(){console.log("hello world")}', {language: 'javascript'}).value;
+});
+
+
 loginRouter.post("/api/v1/login", async (ctx)=> {
     const username = (await ctx.request.body().value).get("username");
     ctx.response.headers.append("HX-Trigger", JSON.stringify({'set-seed': username}));
diff --git a/src/shared.ts b/src/shared.ts
index 1d2e67b..09d1220 100644
--- a/src/shared.ts
+++ b/src/shared.ts
@@ -1,4 +1,4 @@
-interface QuestionSource {
+export interface QuestionSource {
     toString(): string;
 }