title: Get the first elements of a list of tuples
body: <p>I have this list of tuples</p>
  
  <pre><code>[(4,'a'), (1,'b'), (2,'c'), (2,'a'), (1,'d'), (4,'e')]
  </code></pre>
  
  <p>I want to get the first elements of every tuple then replicate it to make the following: "aaaabccaadeeee" </p>
  
  <p>I came up with this code, but it only gives me the replicate of the first tuple.</p>
  
  <pre><code>replicate  (fst ( head [(4,'a'), (1,'b')])) ( snd ( head [(4,'a'), (1,'b')]))
  --output is: "aaaa"
  </code></pre>
  
  <p>I was thinking to use map for to get the replicate of every tuple, but I didn't succeed.</p>