"""
Exercise 2: Summary Ranges (LeetCode 228)

nums is sorted with distinct values. Return the smallest list of ranges
covering all numbers: "a->b" for a run, "a" for a single number.

  summary_ranges([0, 1, 2, 4, 5, 7]) -> ["0->2", "4->5", "7"]
"""

def summary_ranges(nums):
    # TODO
    return []


# --- self-check: do not modify below this line ---
a = summary_ranges([0, 1, 2, 4, 5, 7])
b = summary_ranges([0, 2, 3, 4, 6, 8, 9])
print(a, b, summary_ranges([]))
print("PASS" if a == ["0->2", "4->5", "7"] and b == ["0", "2->4", "6", "8->9"] and summary_ranges([]) == [] else "FAIL")