Fixed build issue

datastruct/elementary/queue/Makefile

@@ -1,11 +1,12 @@
-HEADER =
-SOURCE = queue-en.tex
-OBJECT = queue-en
+SRC = queue
+OBJ = $(SRC)-en.pdf
+OBJ_CN = $(SRC)-zh-cn.pdf
 TEX = xelatex
 
 .PHONY: all
 
-all: pdf
+all: tex
+tex: $(OBJ)
 
 cpp:
 	$(MAKE) cpp -C src
@@ -22,15 +23,9 @@ tool:
 image:
 	$(MAKE) -C img
 
-pdf: image
-	$(TEX) $(OBJECT)
-	$(TEX) $(OBJECT)
-
-tex: pdf
-
-html: image
-	htlatex.bat $(OBJECT) "html, imgdir:img/"
-	mv *.png img/
+%.pdf: %.tex image
+	$(TEX) $<
+	$(TEX) $<
 
 clean:
 	rm -f *.aux *.dvi *.log *.out *.pdf *~

datastruct/elementary/queue/queue-en.tex

@@ -163,8 +163,8 @@ \subsection{Singly linked-list solution}
 class Queue q where
     empty :: q a
     isEmpty :: q a -> Bool
-    push :: q a -> a -> q a     -- Or named as 'snoc', append, push_back
-    pop :: q a -> q a           -- Or named as 'tail', pop_front
+    push :: q a -> a -> q a     -- Or named as 'snoc', append, push\_back
+    pop :: q a -> q a           -- Or named as 'tail', pop\_front
     front :: q a -> a           -- Or named as 'head'
 \end{lstlisting}
 
@@ -1073,8 +1073,8 @@ \subsubsection{Sum up}
 \lstset{language=Haskell}
 \begin{lstlisting}
 data State a = Empty
-             | Reverse Int [a] [a] [a] [a] -- n, f', acc_f' r, acc_r
-             | Append Int [a] [a]          -- n, rev_f', acc
+             | Reverse Int [a] [a] [a] [a] -- n, f', acc\_f' r, acc\_r
+             | Append Int [a] [a]          -- n, rev\_f', acc
              | Done [a] -- result: f ++ reverse r
 \end{lstlisting}