title: battleships game - Haskell
body: <p>I am a Haskell beginner, and I have problem with my homework.
  Assignment of this homework is down below. I really need help.</p>
  
  <p>I must implement the function ships which has 2 arguments. First argument is a list of strings representing play field of one player row by row from top to bottom ('o' - square containing a ship, ' ' - empty square). Second list contains coordinates of squares attacked by second player. Print actual state of a play in the way where every row and column will be labelled by its number or letter, 'o' will be square with ship not attacked yet, 'x' square with ship already attacked, '.' already attacked empty square, ' ' empty square not attacked yet. You can consider that the size of play-field is 10x10. </p>
  
  <pre><code>type Result = [String]
  ships :: Result -&gt; [(Char, Int)] -&gt; Result
  sampleInput = ["  o    o  ",
             "      ooo ",
             "   oo     ",
             "          ",
             "     o    ",
             "     o    ",
             "     o    ",
             "          ",
             "          ",
             "  oooo    "]
  </code></pre>
  
  <p>and this should be an input and output</p>
  
  <pre><code>Prelude&gt;pp(ships sampleInput [('a',1),('d',1),('d',2),('c',1),('b',1),('e',1),('f',1),('g',1),('c',7),('c',10)])
               10  x    o
               9      ooo
               8   oo
               7  .
               6     o
               5     o
               4     o
               3
               2   .
               1..xxxx.
                abcdefghij
  </code></pre>
  
  <p>can someone help me, how the code should look like?</p>