Lists

Popcorn Hack 1: Lists and Indexing

Code Runner Challenge

Lists Popcorn 1 - predict, run, fix the crash

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# CODE_RUNNER: Lists Popcorn 1 - predict, run, fix the crash
items_needed = ["blankets", "socks", "water", "meals"]

print(items_needed[0])                      # Prediction: blankets
print(items_needed[len(items_needed) - 1])  # Prediction: meals
print(len(items_needed))                    # Prediction: 4
print(items_needed[3])                      # Prediction: items_needed[4] raises IndexError (last index is 3). Fixed to [3] -> meals
Lines: 1 Characters: 0
Output
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Popcorn Hack 2: Sum and Average with Accumulator Pattern

Code Runner Challenge

Lists Popcorn 2

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# CODE_RUNNER: Lists Popcorn 2
volunteer_hours = [7, 6, 8, 5, 7, 9]

if len(volunteer_hours) == 0:
    print("No data yet")
else:
    total = 0
    for hours in volunteer_hours:
        total += hours
    print(f"Sum: {total}")

    average = total / len(volunteer_hours)
    print(f"Average: {average}")
Lines: 1 Characters: 0
Output
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Popcorn Hack 3: Frequency Counting and Filtering

Code Runner Challenge

Lists Popcorn 3 - count then filter

View IPYNB Source 
# CODE_RUNNER: Lists Popcorn 3 - count then filter
items_requested = ["blankets", "socks", "meals", "socks", "water", "socks", "meals"]

frequency = {}
for item in items_requested:
    if item in frequency:
        frequency[item] += 1
    else:
        frequency[item] = 1

popular = []
for item in frequency:
    if frequency[item] >= 2:
        popular.append(item)

print(frequency)
print(popular)
Lines: 1 Characters: 0
Output
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Homework: Complete Dataset Analysis

Code Runner Challenge

Lists Homework - indexing, accumulator, count and filter on one dataset

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# CODE_RUNNER: Lists Homework - indexing, accumulator, count and filter on one dataset
donations_by_item = ["blankets", "socks", "blankets", "water", "socks", "blankets",
                     "meals", "socks", "blankets", "water", "blankets", "socks"]
costs = [2, 3, 2, 4, 3, 2, 1, 3, 2, 4, 2, 3]

print(len(donations_by_item))
print(donations_by_item[-1])

total = 0
for cost in costs:
    total += cost
average = total / len(costs)
print(f"Total: {int(total)}")
print(f"Average: {int(average)}")

frequency = {}
for item in donations_by_item:
    if item in frequency:
        frequency[item] += 1
    else:
        frequency[item] = 1
print(frequency)

popular = []
for item in frequency:
    if frequency[item] >= 3:
        popular.append(item)
print(popular)
Lines: 1 Characters: 0
Output
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