ML Prep

Classify values in one pass

Problem

Implement classify_values(xs). Return a dictionary with keys negative, zero, positive_even, and positive_odd. Each value is the count of integers in xs in that category. Use one pass over xs.

Starter code

def classify_values(xs):
    pass
Reveal answer or reference solution
def classify_values(xs):
    out = {"negative": 0, "zero": 0, "positive_even": 0, "positive_odd": 0}
    for x in xs:
        if x < 0:
            out["negative"] += 1
        elif x == 0:
            out["zero"] += 1
        elif x % 2 == 0:
            out["positive_even"] += 1
        else:
            out["positive_odd"] += 1
    return out

Public tests

  • classify_values([-2, 0, 1, 2, 3, 4]) → {'negative': 1, 'zero': 1, 'positive_even': 2, 'positive_odd': 2}
  • classify_values([]) → {'negative': 0, 'zero': 0, 'positive_even': 0, 'positive_odd': 0}

Local history

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