diff --git a/09FindingTheOptimum.tex b/09FindingTheOptimum.tex
index ae0fdd8..3e0aa7d 100644
--- a/09FindingTheOptimum.tex
+++ b/09FindingTheOptimum.tex
@@ -165,7 +165,8 @@ TSP问题没有满意解。
             \node[draw=black, circle, minimum height=25pt] (i) at (0,-2) {$i$};
             \node (b) at (4,0) {};
             \draw[-{Stealth[width=5pt]}] (a)--(j);
-            \draw[{Stealth[width=5pt]}-{Stealth[width=5pt]}] (j)--(i);
+            \draw[-{Stealth[width=5pt]}] (j)..controls (-0.7,-0.5) and (-0.7,-1.5)..(i);
+            \draw[-{Stealth[width=5pt]}] (i)..controls (0.7,-1.5) and (0.7,-0.5)..(j);
             \draw[-{Stealth[width=5pt]}] (j)--(k);
             \draw[-{Stealth[width=5pt]}] (k)--(b);
         \end{tikzpicture}