title: variable declared before cycle do not exist in cycle in c#
body: <p>I am using c#  and I have the flowing problem:
  I decelerated the height variable before for cycle ant it says do not exist in the cycle.</p>
  
  <p>In this part of the code I want the program to store all of the 3rd element of the "data" array except the first, so if the "data" array looks like this: 1,2,3,4,5,6,7,8,9,10,11,12... I want to get: 6,9,12...</p>
  
  <pre><code>static int[] tall()
  {
      int[] data = database();//recalling an array filled with numbers
      int j = 0;
      int[] height;
      for (int i = 6; i &lt; data.Length; )
      {
          i = i + 3;
          j++;
          height[j] = data[i];//Use of unassigned local variable 'height'
      }
      return height;
  }
  </code></pre>