diff --git a/pkg/serializer/calc_price.go b/pkg/serializer/calc_price.go
index 54bae47..2b03e77 100644
--- a/pkg/serializer/calc_price.go
+++ b/pkg/serializer/calc_price.go
@@ -39,7 +39,7 @@ func CalcPrice(total_price int64, total_ruler int32, artworksPrices []*model.Art
 
 	maxId, dirId := findArtworkToAdd(artworksPrices, int64(price))
 
-	if dirId > 0 {
+	if dirId >= 0 {
 		artworksPrices[dirId].Price = artworksPrices[dirId].Price + loss_total_price
 	} else {
 		artworksPrices[maxId].Price = artworksPrices[maxId].Price + loss_total_price
@@ -60,7 +60,7 @@ func CalcPrice(total_price int64, total_ruler int32, artworksPrices []*model.Art
 		}
 	}
 
-	if dirId > 0 {
+	if dirId >= 0 {
 		artworksPrices[dirId].ArtworkPrice = artworksPrices[dirId].ArtworkPrice + loss_artwork_price
 	} else {
 		artworksPrices[maxId].ArtworkPrice = artworksPrices[maxId].ArtworkPrice + loss_artwork_price
@@ -77,7 +77,7 @@ func CalcPrice(total_price int64, total_ruler int32, artworksPrices []*model.Art
 		}
 	}
 
-	if dirId > 0 {
+	if dirId >= 0 {
 		artworksPrices[dirId].CopyrightPrice = artworksPrices[dirId].CopyrightPrice + loss_copyright_price
 	} else {
 		artworksPrices[maxId].CopyrightPrice = artworksPrices[maxId].CopyrightPrice + loss_copyright_price