title: Replacing Odd and Even-indexed characters in a string
body: <p>How can I replace even and odd-indexed letters in my strings? I'd like to replace odd-indexed characters with uppercased letters and even-indexed characters with lowercased ones.</p>
  
  <pre><code>x=input("Enter String: ")
  </code></pre>
  
  <p>How can I modify the inputted string?</p>