App Dev Worksheet: Loops over Lists

App development lesson 19: Loops over lists · Set 860 · 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 = ["Riya", "Meera", "Kabir", "Aman", "Zoya"];
   for (let i = 0; i < names.length; i++) {
     show("Hi, " + names[i]);
   } (a) Hi, Riya (b) Hi, Kabir (c) Hi, Meera (d) Hi, Zoya
2. 2.🔁 What number does this code show?
   let runs = [19, 8, 15, 17];
   let best = 0;
   for (let i = 0; i < runs.length; i++) {
     if (runs[i] > best) {
       best = runs[i];
     }
   }
   show(best);
3. 3.🔁 What number does this code show?
   let marks = [9, 1, 16, 9];
   let total = 0;
   for (let i = 0; i < marks.length; i++) {
     total = total + marks[i];
   }
   show(total);
4. 4.🔁 What number does this code show?
   let scores = [17, 10, 1, 11, 18];
   let total = 0;
   for (let i = 0; i < scores.length; i++) {
     total = total + scores[i];
   }
   show(total);
5. 5.🔁 list.length tells you ___. (a) the first item (b) the biggest item (c) the last item (d) how many items it has
6. 6.🔁 What is the LAST line this code shows?
   let names = ["Zoya", "Arjun", "Riya"];
   for (let i = 0; i < names.length; i++) {
     show("Hi, " + names[i]);
   } (a) Hi, Zoya (b) Hi, Arjun (c) Hi, Riya
7. 7.🔁 What number does this code show?
   let steps = [98, 97, 78, 14];
   let count = 0;
   for (let i = 0; i < steps.length; i++) {
     if (steps[i] >= 70) {
       count = count + 1;
     }
   }
   show(count);
8. 8.🔁 What number does this code show?
   let steps = [46, 35, 63, 82, 24];
   let count = 0;
   for (let i = 0; i < steps.length; i++) {
     if (steps[i] >= 60) {
       count = count + 1;
     }
   }
   show(count);
9. 9.🔁 In for (let i = 0; i < 3; i++), which values does i take? (a) 0, 1, 2, 3 (b) 1, 2, 3 (c) 3 (d) 0, 1, 2
10. 10.🔁 What number does this code show?
    let runs = [15, 18, 3, 6];
    let total = 0;
    for (let i = 0; i < runs.length; i++) {
      total = total + runs[i];
    }
    show(total);
11. 11.🔁 What number does this code show?
    let scores = [19, 1, 8];
    let best = 0;
    for (let i = 0; i < scores.length; i++) {
      if (scores[i] > best) {
        best = scores[i];
      }
    }
    show(best);
12. 12.🔁 A loop over a list of 5 items runs its body how many times? (a) 4 (b) 5 (c) 6 (d) 1
13. 13.🔁 What number does this code show?
    let scores = [25, 21, 48];
    let count = 0;
    for (let i = 0; i < scores.length; i++) {
      if (scores[i] >= 70) {
        count = count + 1;
      }
    }
    show(count);
14. 14.🔁 What is the LAST line this code shows?
    let names = ["Meera", "Riya", "Aman"];
    for (let i = 0; i < names.length; i++) {
      show("Hi, " + names[i]);
    } (a) Hi, Aman (b) Hi, Riya (c) Hi, Meera
15. 15.🔁 Why use a loop to show 100 messages? (a) it is slower (b) it hides them (c) it uses more lines (d) less code to write
16. 16.🔁 What is the LAST line this code shows?
    let names = ["Aman", "Kabir", "Meera"];
    for (let i = 0; i < names.length; i++) {
      show("Hi, " + names[i]);
    } (a) Hi, Aman (b) Hi, Kabir (c) Hi, Meera
17. 17.🔁 What number does this code show?
    let scores = [19, 17, 16, 9, 1];
    let best = 0;
    for (let i = 0; i < scores.length; i++) {
      if (scores[i] > best) {
        best = scores[i];
      }
    }
    show(best);
18. 18.🔁 What number does this code show?
    let scores = [8, 17, 2, 10];
    let total = 0;
    for (let i = 0; i < scores.length; i++) {
      total = total + scores[i];
    }
    show(total);
19. 19.🔁 What number does this code show?
    let marks = [4, 6, 17];
    let total = 0;
    for (let i = 0; i < marks.length; i++) {
      total = total + marks[i];
    }
    show(total);
20. 20.🔁 What number does this code show?
    let scores = [3, 10, 3, 5];
    let total = 0;
    for (let i = 0; i < scores.length; i++) {
      total = total + scores[i];
    }
    show(total);
21. 21.🔁 What number does this code show?
    let marks = [5, 18, 14];
    let total = 0;
    for (let i = 0; i < marks.length; i++) {
      total = total + marks[i];
    }
    show(total);
22. 22.🔁 What is the LAST line this code shows?
    let names = ["Zoya", "Kabir", "Aman", "Riya", "Arjun"];
    for (let i = 0; i < names.length; i++) {
      show("Hi, " + names[i]);
    } (a) Hi, Kabir (b) Hi, Aman (c) Hi, Zoya (d) Hi, Arjun
23. 23.🔁 What number does this code show?
    let scores = [19, 14, 3, 7, 14];
    let total = 0;
    for (let i = 0; i < scores.length; i++) {
      total = total + scores[i];
    }
    show(total);
24. 24.🔁 What does a loop do? (a) deletes code (b) repeats code (c) saves photos (d) draws icons
25. 25.🔁 What number does this code show?
    let runs = [9, 11, 13];
    let total = 0;
    for (let i = 0; i < runs.length; i++) {
      total = total + runs[i];
    }
    show(total);
26. 26.🔁 What is the LAST line this code shows?
    let names = ["Riya", "Aman", "Kabir"];
    for (let i = 0; i < names.length; i++) {
      show("Hi, " + names[i]);
    } (a) Hi, Kabir (b) Hi, Aman (c) Hi, Riya
27. 27.🔁 What number does this code show?
    let marks = [15, 92, 74, 39];
    let count = 0;
    for (let i = 0; i < marks.length; i++) {
      if (marks[i] >= 60) {
        count = count + 1;
      }
    }
    show(count);
28. 28.🔁 What number does this code show?
    let scores = [5, 12, 12, 6];
    let best = 0;
    for (let i = 0; i < scores.length; i++) {
      if (scores[i] > best) {
        best = scores[i];
      }
    }
    show(best);
29. 29.🔁 What number does this code show?
    let runs = [10, 12, 10, 17, 18];
    let total = 0;
    for (let i = 0; i < runs.length; i++) {
      total = total + runs[i];
    }
    show(total);
30. 30.🔁 What number does this code show?
    let steps = [55, 94, 15, 24];
    let count = 0;
    for (let i = 0; i < steps.length; i++) {
      if (steps[i] >= 40) {
        count = count + 1;
      }
    }
    show(count);
31. 31.🔁 What number does this code show?
    let scores = [18, 16, 15];
    let total = 0;
    for (let i = 0; i < scores.length; i++) {
      total = total + scores[i];
    }
    show(total);
32. 32.🔁 What number does this code show?
    let steps = [4, 14, 11, 7];
    let total = 0;
    for (let i = 0; i < steps.length; i++) {
      total = total + steps[i];
    }
    show(total);
33. 33.🔁 What number does this code show?
    let scores = [10, 1, 14];
    let total = 0;
    for (let i = 0; i < scores.length; i++) {
      total = total + scores[i];
    }
    show(total);
34. 34.🔁 What number does this code show?
    let marks = [13, 18, 4];
    let best = 0;
    for (let i = 0; i < marks.length; i++) {
      if (marks[i] > best) {
        best = marks[i];
      }
    }
    show(best);
35. 35.🔁 What number does this code show?
    let marks = [13, 23, 22];
    let count = 0;
    for (let i = 0; i < marks.length; i++) {
      if (marks[i] >= 60) {
        count = count + 1;
      }
    }
    show(count);
36. 36.🔁 What number does this code show?
    let scores = [18, 3, 14, 17, 3];
    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 = [10, 19, 4];
    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 = [30, 90, 37];
    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 marks = [37, 36, 97];
    let count = 0;
    for (let i = 0; i < marks.length; i++) {
      if (marks[i] >= 70) {
        count = count + 1;
      }
    }
    show(count);
40. 40.🔁 What number does this code show?
    let marks = [46, 69, 72, 62];
    let count = 0;
    for (let i = 0; i < marks.length; i++) {
      if (marks[i] >= 60) {
        count = count + 1;
      }
    }
    show(count);

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