Battleship

Please note: read the guideline before starting.

Let's implement a class that provides an interface to create and modify the field for Battleship game. It should have the following public methods:

• __init__(self, ships), to create a field with given ships;
• fire(self, ceil), to simulate a shot to cell.

Consider a field as a matrix 10x10.

x	x	x	x	~	□	□	~	□	□	
~	~	~	~	~	~	~	~	~	~	
□	~	~	~	□	□	□	~	□	□	
□	~	~	~	~	~	~	~	~	~	
□	~	~	~	~	~	~	~	~	~	
~	~	~	~	~	~	~	~	~	~	
~	~	~	~	~	~	~	~	~	~	
~	~	~	~	~	~	~	□	~	□	
~	~	~	~	~	~	~	~	~	~	
~	~	~	~	~	~	~	□	~	□

The first coordinate of each cell is the number of the row.

The second is the number of the column.

The upper-left corner has coordinates (0, 0).

The lower-right has coordinates (9, 9).

We will define a ship by the coordinates of its ends.

For example, a ship marked with crosses has ends with coordinates (0, 0) and (0, 3), so a tuple ((0, 0), (0, 3)) corresponds to it.

Implement the class Battleship that takes a list of ships. Each ship is represented by a such tuple.

Example:

battle_ship = Battleship(
    ships=[
        ((0, 0), (0, 3)),
        ((0, 5), (0, 6)),
        ((0, 8), (0, 9)),
        ((2, 0), (4, 0)),
        ((2, 4), (2, 6)),
        ((2, 8), (2, 9)),
        ((9, 9), (9, 9)),
        ((7, 7), (7, 7)),
        ((7, 9), (7, 9)),
        ((9, 7), (9, 7)),
    ]
)

This field can be represented as follows:

□	□	□	□	~	□	□	~	□	□	
~	~	~	~	~	~	~	~	~	~	
□	~	~	~	□	□	□	~	□	□	
□	~	~	~	~	~	~	~	~	~	
□	~	~	~	~	~	~	~	~	~	
~	~	~	~	~	~	~	~	~	~	
~	~	~	~	~	~	~	~	~	~	
~	~	~	~	~	~	~	□	~	□	
~	~	~	~	~	~	~	~	~	~	
~	~	~	~	~	~	~	□	~	□

Here ~ is an empty cell and □ is a deck.

If the fire method is called it should return one of the following strings:

• "Miss!" - when there is no ship in the given ceil;
• "Hit!" - when there is a deck in the ceil, but the corresponding ship still have another alive deck;
• "Sunk!" - when there is the last alive deck.

Example:

print(
    battle_ship.fire((0, 4)),  # Miss!
    battle_ship.fire((0, 3)),  # Hit!
    battle_ship.fire((0, 2)),  # Hit!
    battle_ship.fire((0, 1)),  # Hit!
    battle_ship.fire((0, 0)),  # Sunk!
)

Note: follow the created template and implement already declared methods. Feel free to add your own methods to extend the functionality.

Extra tasks:

1. Print field

It is recommended to implement this method, it will greatly simplify the debugging process!

Create method print_field which prints all cells of the field line by line.

• Use ~ symbol for empty cells
• Use □ symbol for alive decks. You can print it using the unicode symbol:

print(u"\u25A1")

• Use * for hit decks of the alive ship
• Use x for decks of the drowned ship

Feel free to use other symbols instead of these if you think it'd be better.

2. Validate input

Write protected method _validate_field that should check the following conditions after creating a field in the __init__ method:

• the total number of the ships should be 10;
• there should be 4 single-deck ships;
• there should be 3 double-deck ships;
• there should be 2 three-deck ships;
• there should be 1 four-deck ship;
• ships shouldn't be located in the neighboring cells (even if cells are neighbors by diagonal).

Note: Check your code using this checklist before pushing your solution.