title: How to swap value index in NSArray
body: <p>I have <code>NSArray</code>. I have some value inside that array.</p>
  
  <pre><code>NSArray *testArray = [NSArray arrayWithObjects:@"Test 1", @"Test 2", @"Test 3", @"Test 4", @"Test 5", nil];
  NSLog(@"%@", testArray);
  </code></pre>
  
  <p>Result is like bellow :</p>
  
  <pre><code>(
  "Test 1",
  "Test 2",
  "Test 3",
  "Test 4",
  "Test 5"
  )
  </code></pre>
  
  <p>Now I want the result like this :</p>
  
  <pre><code>(
  "Test 3",
  "Test 5",
  "Test 1",
  "Test 2",
  "Test 4"
  )
  </code></pre>
  
  <p>Is there any way to do it without re-initialize the array? Can I swap the value of this array ?</p>