"""
Exercise 1: Best Time to Buy and Sell Stock II (LeetCode 122)

You may buy and sell many times (hold at most one share). Return the max
profit. Greedy: take every positive day-to-day increase.
"""

def max_profit(prices):
    # TODO
    return 0


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