Mountain Scape

The mission is in Blocked Mode.
Access to the solutions is blocked for a day or two (even after you share your own), until we'll have enough solutions for you to check.
All users who've solved the mission will get the notifications about their opening.

You are given the coordinates of the top of the triangle as input values.

- The slope angle is 45 degrees.
- The base is always on the x-axis.

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NOTE:
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- The sum of the X and Y coordinates is always even. (e.g. (1, 3) (0, 2) ...)

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Example:
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mountain_scape([(1, 1), (4, 2), (7, 3)]) == 13 mountain_scape([(0, 2), (5, 3), (7, 5)]) == 29 mountain_scape([(1, 3), (5, 3), (5, 5), (8, 4)]) == 37

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Input:
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A list of a tuple of two integers.

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Output:
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An integer.

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Precondition:
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- 0 ≤ x ≤ 100
- 1 ≤ y ≤ 50
- (x+y) % 2 == 0
- 1 ≤ len(tops) ≤ 50