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Lazy IITians

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Question sets

  1. 1
    Write a api on notepad , take 2 input and return the output as the sum of the 2 numbers.
    Times asked 2
    Official solution

    SimpleNaya Flask route: URL, method, auth if needed, query, jsonify. Postman pehle.

    Examiner number/filter change easy rakhna. CORS. Frontend tabhi jab bole.

    Status codes sahi. Password JSON mein nahi.

    Examiner 2 cheezein: simple desi line + tumhare project ki exact file.

    Pehle ID, GitHub, portal ZIP. Phir run: Redis + Flask + worker + beat + Vue. Feature demo: login, RBAC, cache hit/miss, Celery mail, search.

    Line pe ungli: input kahan, kaunsa check, query/cache/task, JSON/UI. Copilot band. Jo nahi kiya honestly bolo + kaise add karte.

    Example

    @app.route('/api/sum', methods=['POST'])
    def sum_num():
        d = request.get_json()
        return jsonify(result=d['a'] + d['b'])

    Project example: resources.py new Resource. Test Thunder. Optional Vue fetch.

Advice: Super cool. Very good proctor.
  1. 1
    Ask to change some button position using flex CSS property.
    Times asked 2
    Official solution

    SimpleLive UI change: relevant CSS/HTML template kholo — color, margin, flex, bootstrap class. Save + hard refresh.

    Example

    /* button red */
    .btn-primary { background: red; }
    
    /* center navbar item */
    .navbar { justify-content: center; }

    Viva tipDevTools se pehle try, phir file mein permanent change.

  2. 2
    Ask to explain search API.
    Times asked 2
    Official solution

    SimpleSearch: form/query param → ilike filter → results template.

    Example

    q = request.args.get('q', '').strip()
    lots = Lot.query.filter(Lot.name.ilike(f'%{q}%')).all()
  3. 3
    What is the difference between ilike and like?
    Times asked 2
    Official solution

    SimpleLIKE case-sensitive Postgres. ILIKE insensitive. SQLite LIKE often insensitive.

    Search use ilike.

    Pehle 1-line definition, phir related MAD2 layer (Vue SFC / Flask route / models.py / tasks.py / Redis).

    4-line formula: input kahan se aaya, auth/validation kaunsa, DB ya cache ya Celery, kya return.

    Related mix mat karo — cache ≠ Celery, authentication ≠ authorization, v-if ≠ v-show, Beat ≠ Worker. Follow-up ke liye ek difference ready rakho.

    Project example: Venue.name.ilike(f'%{q}%').

    Project example: Venue.name.ilike(f'%{q}%').

  4. 4
    Advantage of JavaScript. Theory questions are same like previously asked. Gave some suggestion about project improvement.
    Times asked 2
    Official solution

    SimpleTheory = concepts: ORM, MVC, auth vs authz, Jinja inheritance, sessions. 1-line def + project example.

Advice: Very good proctor. Need some understanding of basic code , he may ask to explain one of the API and theory questions mostly same as the previous.
  1. 1
    Vue 3 updates / patches from vue 2
    Times asked 2
    Official solution

    SimpleVue 3 naya engine: Composition API, fragments, better TS, tree-shaking. Vue 2 Options + filters.

    mounted vs onMounted. Filters Vue 3 mein hata — computed/methods.

    Version package.json / Vue.version se dikhao. Jo use kiya uske hooks bolo.

    SPA = ek HTML, Vue Router se views, full reload nahi. MPA = MAD1 Jinja har URL naya HTML.

    Vue Router: routes array, router-view, router-link, meta.auth + beforeEach guard. Dynamic /venues/:id$route.params.id.

    Vite/CLI SFC + npm build dist/. CDN script tag, no SFC. Jo tumne use kiya wahi justify. Flask send_from_directory('dist') production pattern.

    Project example: package.json vue ^3.x. setup() + onMounted fetch.

    Viva tipVersion package.json / Vue.version se dikhao. MAD2 dono allowed usually — jo use kiya uske hooks bolo (mounted vs onMounted).

  2. 2
    And some questions about new things in vue 3 some stream thingy and tree
    Times asked 2
    Official solution

    SimpleVue = UI ka smart assistant. Data badlo, screen khud update. MAD1 Jinja har click pe naya HTML.

    Progressive frontend framework. Components, reactivity, directives.

    MAD2 SPA: ek index.html, Vue Router pages, Flask sirf JSON.

    Fayde: easy, SFC, docs. Vs React: templates HTML-like, course sikhata hai. Vs plain JS: baar-baar DOM mat chhedo.

    Example

    <!-- HelloWorld.vue -->
    <template>
      <h1>{{ msg }}</h1>
    </template>
    <script>
    export default { data() { return { msg: 'Hello' } } }
    </script>

    Project example: Navbar.vue + views (Login, Dashboard). data() / setup() reactive. fetch APIs.

    Viva tipFayde: easy, SFC, reactivity. Vs React: chhota learning curve. Vs plain JS: UI state auto-update.

Advice: Chill guy but the questions he asked weren't in the sheet so wasn't able to prep for them and they were very odd ones this is updated feedback
  1. 1
    - The examiner joined late.
    Times asked 2
    Official solution

    SimpleJOIN related tables ek result mein. Inner = match only; left = left side sab + match.

    Example

    db.session.query(Booking, User).join(User).filter(User.id == uid).all()
  2. 2
    - Explained the entire app with all features, and this took 20 minutes.
    Times asked 2
    Official solution

    SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.

  3. 3
    - What is Redis? Why is it faster?
    Times asked 1
    Official solution

    SimpleRedis fridge pe sticky note hai — poori kitchen (database) kholne ki zarurat nahi.

    Redis in-memory key-value store hai. Data RAM mein rehta hai, isliye disk wale SQLite/Postgres se kai guna tez.

    MAD2 mein Redis do kaam karta hai:
    1) Cache — same venue/show/dashboard JSON baar-baar DB se mat nikaalo.
    2) Celery message broker — Flask task queue mein daalta hai, worker uthata hai.

    Source of truth database hi hai. Redis band ho to cache miss ho jaata hai aur Celery queue ruk sakti hai. Crash pe cache gayab ho sakta hai — isliye important data sirf Redis mein mat rakho.

    Example

    import redis
    r = redis.Redis(host='localhost', port=6379, db=0)
    r.set('venues', json.dumps(data), ex=30)
    print(r.get('venues'))

    Project example: GET /api/venues pehle Redis dekho. Miss pe SQLAlchemy query, phir SET with timeout. Celery worker Redis list se daily reminder uthata hai.

    Viva tipCache ke liye db=1, broker ke liye db=0 rakhna smart hai taaki keys mix na hon. Viva mein redis-cli ping → PONG dikhana strong hai.

  4. 4
    - What is hashing.?
    Times asked 2
    Official solution

    SimpleMAD1 mein common: Werkzeug generate_password_hash — default usually pbkdf2:sha256. Apna code dikhao.

    Example

    from werkzeug.security import generate_password_hash
    print(generate_password_hash('secret'))  # pbkdf2:sha256:...
  5. 5
    - What is indexing in databases?
    Times asked 1
    Official solution

    SimpleIndex kitab ki suchi — search tez, write thoda mehnga.

    B-tree typically. filter wale columns, FKs. Over-index mat.

    joinedload N+1 alag.

    Pehle 1-line definition, phir related MAD2 layer (Vue SFC / Flask route / models.py / tasks.py / Redis).

    4-line formula: input kahan se aaya, auth/validation kaunsa, DB ya cache ya Celery, kya return.

    Related mix mat karo — cache ≠ Celery, authentication ≠ authorization, v-if ≠ v-show, Beat ≠ Worker. Follow-up ke liye ek difference ready rakho.

    Example

    db.Column(db.String(80), index=True)
    db.Index('ix_name_city', User.name, User.city)

    Project example: email index, venue.name search index.

  6. 6
    - What is memoization?
    Times asked 1
    Official solution

    SimpleMemoize = function(args) ka answer copy. Caching broader (HTTP, Redis, page).

    Fibonacci textbook. Flask @cache.memoize. cached whole view.

    Redis in-memory key-value store hai — fridge pe sticky note, poori kitchen (SQL database) har baar mat kholo.

    MAD2 mein Redis do kaam: (1) cache — same venues/shows/dashboard JSON baar-baar DB se nahi (2) Celery broker — Flask task queue mein daalta hai, worker uthata hai.

    Flow: cache.get(key) → hit pe return, miss pe SQLAlchemy + SET with timeout. Admin write ke baad cache.delete, warna stale list.

    Source of truth database hi hai. Redis crash/band = cache miss (app chalni chahiye) + queue ruk sakti hai. Important bookings sirf Redis mein mat rakho.

    Alag: Redis ≠ Memcached (Celery broker nahi). Redis ≠ localStorage (woh browser). redis-cli ping → PONG viva proof.

    Project example: get_user(id) memoize. venues list cached.

  7. 7
    - What is a primary key in a database?
    Times asked 1
    Official solution

    SimplePrimary key row ka unique identity — usually id Integer autoincrement.

    Example

    id = db.Column(db.Integer, primary_key=True)
Advice: No coding-related questions were asked of me , but I explained everything with confidence.
  1. 1
    LVL1 VIVA
    Times asked 2
    Official solution

    SimpleLevel = viva difficulty band. Level 1 usually demo + basics; higher pe live coding + deeper theory.

    Viva tipJo level assign hai uske hisaab se demo + theory ready rakho.

  2. 2
    Asked for ID
    Times asked 2
    Official solution

    SimpleCamera pe clearly college/IITM ID dikhao — naam aur photo match hone chahiye.

    Viva tipPehle se ID haath mein rakho, glare mat aane do. Iske baad GitHub + project run.

  3. 3
    Downloaded in front of him
    Times asked 2
    Official solution

    SimplePehle 1-line definition, phir apne MAD1 project mein file dikhao, phir chhota example.

    Suggested flow1) Concept kya hai?
    2) Mere code mein kahan?
    3) Example / demo
    4) Edge case

    Example

    # related file: models.py / routes / template
    # formula: request → check/auth → DB → render/redirect

    Viva tipExact line yaad nahi to honestly related part dikhao. Bluff mat karo.

  4. 4
    Asked me to show functionality one by one
    Times asked 2
    Official solution

    SimpleDemo script pehle se practice: 5–7 min, Admin + User roles, saare mandatory features.

    Suggested flow1) Register/login user
    2) Admin login — CRUD
    3) Approval/blacklist
    4) Booking/apply + edge case
    5) Search
    6) Logout

    Viva tipBolte-bolte dikhao. Code tab kholna jab poochhein.

  5. 5
    then asked about authentication settings
    Times asked 2
    Official solution

    SimpleAuthentication: tu kaun hai? (login). Authorization: tujhe permission hai? (role check).

    Example

    # auth
    if check_password_hash(user.password, pwd):
        session['user_id'] = user.id
    
    # authz
    if user.role != 'admin':
        abort(403)
  6. 6
    asked me about token and how it was setup-i used flask security explained unquifier
    Times asked 2
    Official solution

    SimpleFlask lightweight Python web framework — routes, request/response, templates. MAD1 ka backend yahi hai.

    Example

    from flask import Flask
    app = Flask(__name__)
    
    @app.route('/')
    def home():
        return 'Hello'

    Viva tipFlask micro hai: jo chahiye (DB, login, forms) khud jodte ho.

  7. 7
    then asked me to copy paste the home url to another browser and asked me why does the link not work there like extension to authentication
    Times asked 2
    Official solution

    SimpleAuthentication: tu kaun hai? (login). Authorization: tujhe permission hai? (role check).

    Example

    # auth
    if check_password_hash(user.password, pwd):
        session['user_id'] = user.id
    
    # authz
    if user.role != 'admin':
        abort(403)
  8. 8
    also saw the token being generated in db
    Times asked 2
    Official solution

    SimpleJWT teen tukde ki signed chitthi: header.payload.signature. Padhi ja sakti hai, badli nahi ja sakti.

    Encoded (Base64) + signed, encrypted nahi (JWE alag). Payload mein password mat daalo — koi jwt.io pe dekh lega.

    Login pe server secret se HMAC (HS256). Har API Authorization: Bearer <token>.
    Expiry exp. Change payload → signature fail → 401.

    Session MAD1 server yaad rakhta. JWT MAD2 client rakhta, server stateless-ish.

    Example

    eyJhbGciOiJIUzI1NiJ9.{"sub":1,"role":"admin"}.signature
    # Authorization: Bearer <token>

    Project example: POST /login → token LS. fetch interceptor header. @jwt_required APIs.

    Viva tipAlgo HS256. Secret env var. jwt.io pe payload dikhao, secret public site pe mat paste.

  9. 9
    asked to show csv export and open the file
    Times asked 2
    Official solution

    SimpleClick → Celery → worker CSV → email/download. Columns verify.

    csv module. Auth required. Don't freeze UI — 202 + poll.

    Examiner 2 cheezein: simple desi line + tumhare project ki exact file.

    Pehle ID, GitHub, portal ZIP. Phir run: Redis + Flask + worker + beat + Vue. Feature demo: login, RBAC, cache hit/miss, Celery mail, search.

    Line pe ungli: input kahan, kaunsa check, query/cache/task, JSON/UI. Copilot band. Jo nahi kiya honestly bolo + kaise add karte.

    Example

    @celery.task
    def export_venues_csv(user_id):
        rows = Venue.query.all()
        # csv.writer, mail.send
        return 'ok'

    Project example: Admin export venues. MailHog attach ya file open.

    Viva tipNetwork tab mein job trigger API dikhao, phir MailHog/file open karke columns verify karo.

  10. 10
    asked me to change time in celery task to run it
    Times asked 2
    Official solution

    SimpleCelery = background naukri. HTTP request ko 10 second email bhejne ke liye mat rokna.

    Distributed task queue: aap function ko abhi nahi, worker process mein later/retry/schedule pe chalaate ho.

    MAD2 typical jobs: daily reminder mail, monthly HTML report, user-triggered CSV export.

    Web request 200ms hona chahiye. 10,000 emails request thread mein = timeout. Worker alag CPU pe kaam kare.

    Redis broker chahiye. Beat alag process schedule ke liye.

    Example

    @celery.task
    def daily_reminder():
        for u in User.query.filter_by(active=True):
            send_mail(u.email, 'Book something today!')

    Project example: User Export click → 202 Accepted. Worker CSV + email. Daily 6pm Beat reminder.

    Viva tipWorker + Redis bina Beat ke user-triggered chalega. Scheduled jobs ke liye Beat bhi chahiye.

  11. 11
    checked my frontend files and asked me how would i create a new view component or view and connect it to backend
    Times asked 2
    Official solution

    SimpleMAD1 frontend usually Jinja templates + HTML/CSS/Bootstrap (+ thoda JS). MAD2 pe Vue ho to clearly bolo.

  12. 12
    asked about cache
    Times asked 2
    Official solution

    SimpleCache = pehli baar hisaab karke copy rakh lo, doosri baar copy dikha do.

    Baar-baar same expensive kaam (DB query, counting bookings) mat karo. Result Redis jaise store mein timeout ke saath rakh do.

    Cache hit: key mil gayi, DB skip. Cache miss: DB se lao, SET karo, return karo.

    Tradeoff: speed vs stale data. Admin naya venue add kare aur cache 50s ka ho to user purani list dekh sakta hai — isliye write pe invalidation zaroori hai.

    Browser cache, Flask-Caching, Redis alag layers hain. MAD2 examiner Redis + @cache.cached code dekhta hai.

    Example

    @cache.cached(timeout=50, query_string=True)
    @app.route('/api/shows')
    def shows():
        return jsonify([s.serialize() for s in Show.query.all()])

    Project example: Admin dashboard counts / venues list cache. Create/update/delete ke baad cache.delete('venues').

    Viva tipprint('DB queried') function ke andar laga ke miss/hit demo karo — hit pe print nahi chalega.

  13. 13
    theory asked:
    Times asked 2
    Official solution

    SimpleTheory = concepts: ORM, MVC, auth vs authz, Jinja inheritance, sessions. 1-line def + project example.

  14. 14
    difference in put and patch
    Times asked 2
    Official solution

    SimplePOST naya janam (har baar naya id). PUT poori photo replace. PATCH sticker chipkao.

    POST create, not idempotent. PUT full update, idempotent. PATCH partial.

    POST ki jagah PUT se REST semantics toot. GET typically no body.

    CRUD map: POST create, GET read, PUT/PATCH update, DELETE delete.

    Pehle 1-line definition, phir related MAD2 layer (Vue SFC / Flask route / models.py / tasks.py / Redis).

    4-line formula: input kahan se aaya, auth/validation kaunsa, DB ya cache ya Celery, kya return.

    Related mix mat karo — cache ≠ Celery, authentication ≠ authorization, v-if ≠ v-show, Beat ≠ Worker. Follow-up ke liye ek difference ready rakho.

    Example

    POST /api/venues
    PUT  /api/venues/1   {all fields}
    PATCH /api/venues/1 {only name}

    Project example: POST /api/venues create. PUT /venues/1 saari fields. PATCH sirf name.

  15. 15
    what are vue methods and its comparison to properties not props im not sure
    Times asked 2
    Official solution

    SimpleVue = UI ka smart assistant. Data badlo, screen khud update. MAD1 Jinja har click pe naya HTML.

    Progressive frontend framework. Components, reactivity, directives.

    MAD2 SPA: ek index.html, Vue Router pages, Flask sirf JSON.

    Fayde: easy, SFC, docs. Vs React: templates HTML-like, course sikhata hai. Vs plain JS: baar-baar DOM mat chhedo.

    Example

    <!-- HelloWorld.vue -->
    <template>
      <h1>{{ msg }}</h1>
    </template>
    <script>
    export default { data() { return { msg: 'Hello' } } }
    </script>

    Project example: Navbar.vue + views (Login, Dashboard). data() / setup() reactive. fetch APIs.

    Viva tipFayde: easy, SFC, reactivity. Vs React: chhota learning curve. Vs plain JS: UI state auto-update.

  16. 16
    what are vue directives
    Times asked 2
    Official solution

    SimpleDirectives Vue ke special attributes — HTML ko superpower.

    v-if/else/show, v-for, v-bind (:), v-on (@), v-model, v-html (XSS), v-cloak, v-slot.

    :src = v-bind:src. @click = v-on:click.

    Custom directives bhi (v-focus) — course basics kaafi.

    Example

    <p v-if="ok">Yes</p>
    <li v-for="u in users" :key="u.id">{{ u.name }}</li>
    <input v-model="email">
    <img :src="url">

    Project example: List v-for :key. Form v-model. Admin v-if. Image :src.

    Viva tip: src ke liye v-bind:src ka shorthand. @click = v-on:click.

  17. 17
    rest i dont recall but were in middle of conversation
    Times asked 2
    Official solution

    SimplePehle 1-line definition, phir apne MAD1 project mein file dikhao, phir chhota example.

    Suggested flow1) Concept kya hai?
    2) Mere code mein kahan?
    3) Example / demo
    4) Edge case

    Example

    # related file: models.py / routes / template
    # formula: request → check/auth → DB → render/redirect

    Viva tipExact line yaad nahi to honestly related part dikhao. Bluff mat karo.

Advice: be thorough with your code, know where is what
  1. 1
    which database have u used
    Times asked 1
    Official solution

    SimpleSQLite file-based DB — setup easy, MAD1 ke liye perfect. Production heavy traffic pe Postgres better.

    Example

    SQLALCHEMY_DATABASE_URI = 'sqlite:///app.db'
  2. 2
    what is relational database
    Times asked 2
    Official solution

    SimpleRelational DB tables + rows + columns, relations FK se. SQL se query. SQLite/Postgres examples.

    Example

    users(id, email)
    bookings(id, user_id FK → users.id)

    Viva tipVs NoSQL: fixed schema + joins strong; documents flexible but joins weak.

  3. 3
    what is nosql
    Times asked 1
    Official solution

    SimpleNoSQL = non-relational store (documents/key-value). Flexible schema, joins weak. MongoDB/Redis examples. MAD1 usually SQLite relational.

  4. 4
    He joined 5 min late, yet the viva ending within 20 mins
    Times asked 2
    Official solution

    SimpleJOIN related tables ek result mein. Inner = match only; left = left side sab + match.

    Example

    db.session.query(Booking, User).join(User).filter(User.id == uid).all()
  5. 5
    No coding questions asked
    Times asked 4
    Official solution

    SimpleLive coding: notepad/editor mein chhota Flask route / Jinja loop / model field. Calm raho, run karke dikhao.

  1. 1
    exact same questions as mentioned in the other entries for this proctor
    Times asked 2
    Official solution

    SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.

  2. 2
    very chill dude
    Times asked 2
    Official solution

    SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.

  3. 3
    did not ask me to code anything at all
    Times asked 2
    Official solution

    SimpleLive Flask coding: chhota route likho, save, browser/curl se test. Syntax error terminal mein padho.

    Example

    @app.route('/ping')
    def ping():
        return jsonify(ok=True)
    
    @app.route('/even/<int:n>')
    def even(n):
        return 'even' if n % 2 == 0 else 'odd'
  4. 4
    he joined 7 mins late, yet the viva was completed by the 25 min mark, meaning it only lasted 18 mins
    Times asked 2
    Official solution

    SimpleJOIN related tables ek result mein. Inner = match only; left = left side sab + match.

    Example

    db.session.query(Booking, User).join(User).filter(User.id == uid).all()
Advice: just do the questions mentioned by others for level2_86 or l2_86
  1. 1
    Implement functionality such that the user can't book same parking lot if he has an already active booking
    Times asked 2
    Official solution

    SimpleNaya Flask route: URL, method, auth if needed, query, jsonify. Postman pehle.

    Examiner number/filter change easy rakhna. CORS. Frontend tabhi jab bole.

    Status codes sahi. Password JSON mein nahi.

    Examiner 2 cheezein: simple desi line + tumhare project ki exact file.

    Pehle ID, GitHub, portal ZIP. Phir run: Redis + Flask + worker + beat + Vue. Feature demo: login, RBAC, cache hit/miss, Celery mail, search.

    Line pe ungli: input kahan, kaunsa check, query/cache/task, JSON/UI. Copilot band. Jo nahi kiya honestly bolo + kaise add karte.

    Example

    @app.route('/api/sum', methods=['POST'])
    def sum_num():
        d = request.get_json()
        return jsonify(result=d['a'] + d['b'])

    Project example: resources.py new Resource. Test Thunder. Optional Vue fetch.

  2. 2
    Vue memo
    Times asked 2
    Official solution

    SimpleVue = UI ka smart assistant. Data badlo, screen khud update. MAD1 Jinja har click pe naya HTML.

    Progressive frontend framework. Components, reactivity, directives.

    MAD2 SPA: ek index.html, Vue Router pages, Flask sirf JSON.

    Fayde: easy, SFC, docs. Vs React: templates HTML-like, course sikhata hai. Vs plain JS: baar-baar DOM mat chhedo.

    Example

    <!-- HelloWorld.vue -->
    <template>
      <h1>{{ msg }}</h1>
    </template>
    <script>
    export default { data() { return { msg: 'Hello' } } }
    </script>

    Project example: Navbar.vue + views (Login, Dashboard). data() / setup() reactive. fetch APIs.

    Viva tipFayde: easy, SFC, reactivity. Vs React: chhota learning curve. Vs plain JS: UI state auto-update.

  3. 3
    Tree smth idr
    Times asked 2
    Official solution

    SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.

  4. 4
    That's all I remember ig 1 2 more he had asked
    Times asked 2
    Official solution

    SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.

Advice: He's pretty chill ig he was in call in bw but I didn't expect these questions coz it wasn't there in the sheets looks like he got a new set of questions be confident and stay truthful about ur implementation but not too honest atb
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