Create a style with less loops

The requirement is this, I want to set a different background map for a carousel diagram, because each picture of the background map is not the same, so you need to customize the picture path for each individual element.
Then think of the less syntax has a mixin mechanism, thus implementing a recursive function,
Then the corresponding file name is placed according to this rule, banner1-bg.png, banner2-bg.png,,,,,,

Post the Code:

1 @basePicUrl: ******/img/banner;2 . BG (@a){3 [Email Protected]{a} {4 Background-image:url (' @{basepicurl}@{a}-bg.png ');5 Filter:progid:DXImageTransform.Microsoft.AlphaImageLoader (src= "' @{Basepicurl}@{a}-bg.png ' ", sizingmethod=" scale ");6 }7 }8 . Loop (@counter) when (@counter > 0){9 . BG (@counter);Ten . Loop (@counter-1); One} A . Loop (4);

Create a style with less loops