App Dev Worksheet: Loops over Lists

App development lesson 19: Loops over lists · Set 615 · 40 questions

Developer's tip (One by one): for (let i = 0; i < list.length; i++) visits every item, from position 0. Total: add each item. Count: add 1 when the test is true. Best: keep the biggest so far. The body runs once per item: a list of 5 runs it 5 times.

1. 1.🔁 What is the LAST line this code shows?
   let names = ["Arjun", "Meera", "Aman", "Kabir", "Zoya"];
   for (let i = 0; i < names.length; i++) {
     show("Hi, " + names[i]);
   } (a) Hi, Meera (b) Hi, Aman (c) Hi, Arjun (d) Hi, Zoya
2. 2.🔁 What number does this code show?
   let marks = [20, 5, 3];
   let total = 0;
   for (let i = 0; i < marks.length; i++) {
     total = total + marks[i];
   }
   show(total);
3. 3.🔁 What is the LAST line this code shows?
   let names = ["Riya", "Aman", "Zoya"];
   for (let i = 0; i < names.length; i++) {
     show("Hi, " + names[i]);
   } (a) Hi, Zoya (b) Hi, Riya (c) Hi, Aman
4. 4.🔁 A loop over a list of 5 items runs its body how many times? (a) 1 (b) 5 (c) 4 (d) 6
5. 5.🔁 list.length tells you ___. (a) the last item (b) how many items it has (c) the first item (d) the biggest item
6. 6.🔁 What is the LAST line this code shows?
   let names = ["Kabir", "Aman", "Meera"];
   for (let i = 0; i < names.length; i++) {
     show("Hi, " + names[i]);
   } (a) Hi, Kabir (b) Hi, Meera (c) Hi, Aman
7. 7.🔁 What number does this code show?
   let steps = [11, 8, 2];
   let best = 0;
   for (let i = 0; i < steps.length; i++) {
     if (steps[i] > best) {
       best = steps[i];
     }
   }
   show(best);
8. 8.🔁 What number does this code show?
   let steps = [5, 16, 13];
   let total = 0;
   for (let i = 0; i < steps.length; i++) {
     total = total + steps[i];
   }
   show(total);
9. 9.🔁 What number does this code show?
   let steps = [54, 97, 94];
   let count = 0;
   for (let i = 0; i < steps.length; i++) {
     if (steps[i] >= 50) {
       count = count + 1;
     }
   }
   show(count);
10. 10.🔁 What number does this code show?
    let marks = [36, 39, 51, 56, 34];
    let count = 0;
    for (let i = 0; i < marks.length; i++) {
      if (marks[i] >= 60) {
        count = count + 1;
      }
    }
    show(count);
11. 11.🔁 What is the LAST line this code shows?
    let names = ["Arjun", "Meera", "Riya", "Zoya", "Kabir"];
    for (let i = 0; i < names.length; i++) {
      show("Hi, " + names[i]);
    } (a) Hi, Meera (b) Hi, Kabir (c) Hi, Riya (d) Hi, Arjun
12. 12.🔁 What number does this code show?
    let runs = [19, 2, 13, 5, 4];
    let total = 0;
    for (let i = 0; i < runs.length; i++) {
      total = total + runs[i];
    }
    show(total);
13. 13.🔁 What number does this code show?
    let scores = [15, 12, 9, 8, 4];
    let total = 0;
    for (let i = 0; i < scores.length; i++) {
      total = total + scores[i];
    }
    show(total);
14. 14.🔁 What number does this code show?
    let runs = [97, 48, 66];
    let count = 0;
    for (let i = 0; i < runs.length; i++) {
      if (runs[i] >= 70) {
        count = count + 1;
      }
    }
    show(count);
15. 15.🔁 What number does this code show?
    let marks = [7, 7, 8, 19];
    let total = 0;
    for (let i = 0; i < marks.length; i++) {
      total = total + marks[i];
    }
    show(total);
16. 16.🔁 Why use a loop to show 100 messages? (a) it hides them (b) it is slower (c) less code to write (d) it uses more lines
17. 17.🔁 What is the LAST line this code shows?
    let names = ["Meera", "Zoya", "Arjun"];
    for (let i = 0; i < names.length; i++) {
      show("Hi, " + names[i]);
    } (a) Hi, Arjun (b) Hi, Meera (c) Hi, Zoya
18. 18.🔁 What number does this code show?
    let marks = [48, 24, 27, 61];
    let count = 0;
    for (let i = 0; i < marks.length; i++) {
      if (marks[i] >= 70) {
        count = count + 1;
      }
    }
    show(count);
19. 19.🔁 What number does this code show?
    let runs = [5, 15, 6, 9];
    let total = 0;
    for (let i = 0; i < runs.length; i++) {
      total = total + runs[i];
    }
    show(total);
20. 20.🔁 What is the LAST line this code shows?
    let names = ["Arjun", "Kabir", "Meera", "Zoya"];
    for (let i = 0; i < names.length; i++) {
      show("Hi, " + names[i]);
    } (a) Hi, Meera (b) Hi, Kabir (c) Hi, Zoya (d) Hi, Arjun
21. 21.🔁 What number does this code show?
    let steps = [8, 12, 3];
    let total = 0;
    for (let i = 0; i < steps.length; i++) {
      total = total + steps[i];
    }
    show(total);
22. 22.🔁 What number does this code show?
    let runs = [40, 25, 59, 33, 74];
    let count = 0;
    for (let i = 0; i < runs.length; i++) {
      if (runs[i] >= 70) {
        count = count + 1;
      }
    }
    show(count);
23. 23.🔁 What number does this code show?
    let scores = [18, 4, 8, 20, 8];
    let best = 0;
    for (let i = 0; i < scores.length; i++) {
      if (scores[i] > best) {
        best = scores[i];
      }
    }
    show(best);
24. 24.🔁 What number does this code show?
    let marks = [3, 5, 20, 15];
    let total = 0;
    for (let i = 0; i < marks.length; i++) {
      total = total + marks[i];
    }
    show(total);
25. 25.🔁 What is the LAST line this code shows?
    let names = ["Riya", "Arjun", "Zoya", "Meera"];
    for (let i = 0; i < names.length; i++) {
      show("Hi, " + names[i]);
    } (a) Hi, Riya (b) Hi, Meera (c) Hi, Zoya (d) Hi, Arjun
26. 26.🔁 What number does this code show?
    let scores = [14, 9, 1, 5, 9];
    let best = 0;
    for (let i = 0; i < scores.length; i++) {
      if (scores[i] > best) {
        best = scores[i];
      }
    }
    show(best);
27. 27.🔁 What number does this code show?
    let steps = [71, 27, 98, 16];
    let count = 0;
    for (let i = 0; i < steps.length; i++) {
      if (steps[i] >= 40) {
        count = count + 1;
      }
    }
    show(count);
28. 28.🔁 What number does this code show?
    let steps = [5, 19, 14, 6, 13];
    let total = 0;
    for (let i = 0; i < steps.length; i++) {
      total = total + steps[i];
    }
    show(total);
29. 29.🔁 What number does this code show?
    let scores = [17, 8, 5];
    let total = 0;
    for (let i = 0; i < scores.length; i++) {
      total = total + scores[i];
    }
    show(total);
30. 30.🔁 What number does this code show?
    let runs = [50, 12, 26, 88, 56];
    let count = 0;
    for (let i = 0; i < runs.length; i++) {
      if (runs[i] >= 40) {
        count = count + 1;
      }
    }
    show(count);
31. 31.🔁 What does a loop do? (a) saves photos (b) deletes code (c) draws icons (d) repeats code
32. 32.🔁 What number does this code show?
    let runs = [9, 19, 14, 12];
    let best = 0;
    for (let i = 0; i < runs.length; i++) {
      if (runs[i] > best) {
        best = runs[i];
      }
    }
    show(best);
33. 33.🔁 What number does this code show?
    let scores = [96, 75, 86];
    let count = 0;
    for (let i = 0; i < scores.length; i++) {
      if (scores[i] >= 70) {
        count = count + 1;
      }
    }
    show(count);
34. 34.🔁 What number does this code show?
    let scores = [8, 7, 3, 7];
    let total = 0;
    for (let i = 0; i < scores.length; i++) {
      total = total + scores[i];
    }
    show(total);
35. 35.🔁 What is the LAST line this code shows?
    let names = ["Riya", "Kabir", "Meera", "Arjun"];
    for (let i = 0; i < names.length; i++) {
      show("Hi, " + names[i]);
    } (a) Hi, Kabir (b) Hi, Arjun (c) Hi, Riya (d) Hi, Meera
36. 36.🔁 What number does this code show?
    let scores = [19, 3, 4];
    let best = 0;
    for (let i = 0; i < scores.length; i++) {
      if (scores[i] > best) {
        best = scores[i];
      }
    }
    show(best);
37. 37.🔁 What number does this code show?
    let marks = [7, 4, 16, 1, 10];
    let best = 0;
    for (let i = 0; i < marks.length; i++) {
      if (marks[i] > best) {
        best = marks[i];
      }
    }
    show(best);
38. 38.🔁 What number does this code show?
    let scores = [35, 86, 63, 80, 16];
    let count = 0;
    for (let i = 0; i < scores.length; i++) {
      if (scores[i] >= 70) {
        count = count + 1;
      }
    }
    show(count);
39. 39.🔁 What number does this code show?
    let runs = [18, 9, 16];
    let best = 0;
    for (let i = 0; i < runs.length; i++) {
      if (runs[i] > best) {
        best = runs[i];
      }
    }
    show(best);
40. 40.🔁 What number does this code show?
    let scores = [17, 15, 1];
    let total = 0;
    for (let i = 0; i < scores.length; i++) {
      total = total + scores[i];
    }
    show(total);

Free app development lessons, practice and worksheets at talentjr.in/app-development-for-students