diff --git a/utils/g2d/shape.go b/utils/g2d/shape.go
index 0946c70..0b00ddb 100644
--- a/utils/g2d/shape.go
+++ b/utils/g2d/shape.go
@@ -259,7 +259,7 @@ func SearchNotRepeatStraightLine(minLength int, xys ...[2]int) (result [][][2]in
 		}
 		if len(find) == 0 {
 			points = nil
-		} else if len(points) >= minLength {
+		} else if len(points) >= minLength-1 {
 			goto end
 		} else {
 			points = nil