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Katalume
LeetCode × Kaggle, for ML

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Katalume is the training ground for machine learning — solve real ML problems in an in-browser judge, compete in contests, and climb to mastery. LeetCode rigor meets Kaggle depth.

healthcare-feature-mean · main.py
def fit_and_predict(X, y, T, k):
    preds = []
    for t in T:
        d = sorted(
          (dist(t, x), y[i])
          for i, x in enumerate(X))
        top = [lbl for _, lbl in d[:k]]
        preds.append(vote(top))
    return preds
Accepted · 8/8 practice tests
Runtime 114msMemory 28MBEasy

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