public void onBlockAdded(World var1, int var2, int var3, int var4) {
      if(this != Block.stairSingle) {
         super.onBlockAdded(var1, var2, var3, var4);
      }

      int var5 = var1.getBlockId(var2, var3 - 1, var4);
      int var6 = var1.getBlockMetadata(var2, var3, var4);
      int var7 = var1.getBlockMetadata(var2, var3 - 1, var4);
      if(var6 == var7) {
         if(var5 == stairSingle.blockID) {
            var1.setBlockWithNotify(var2, var3, var4, 0);
            var1.setBlockAndMetadataWithNotify(var2, var3 - 1, var4, Block.stairDouble.blockID, var6);
         }

      }
   }