--- a/python/utils.py	Fri Dec 21 17:06:34 2012 -0500
+++ b/python/utils.py	Fri Dec 21 17:29:43 2012 -0500
@@ -174,8 +174,8 @@
     similarity = zeros((m+1,n+1))
     for i in xrange(1,m+1):
         for j in xrange(1,n+1):
-            if distance(l1[i], l2[i])<threshold:
-                similarity[i][j] = similarity(i-1, j-1)+1
+            if distance(l1[i-1], l2[j-1])<threshold:
+                similarity[i][j] = similarity[i-1][j-1]+1
             else:
                 similarity[i][j] = max(similarity[i-1][j], similarity[i][j-1])
     return similarity[-1][-1]