diff --git a/re2/set.cc b/re2/set.cc
index 771061723634a641445333072115da5661067819..76aa7dd840c372260851552293829c9bc6a35993 100644
--- a/re2/set.cc
+++ b/re2/set.cc
@@ -79,7 +79,7 @@ namespace re2
     }
     else
     {
-      elem_.push_back(pair<std::string, re2::Regexp*>(pattern.as_string(), nullptr));
+      elem_.push_back(pair<std::string, re2::Regexp*>(pattern.as_string(), (re2::Regexp*)re));
       size_++;
       // rure_free(re);
       return place_num;
@@ -145,7 +145,6 @@ namespace re2
       {
         if(v == NULL)
         {
-          
           bool result = rure_set_is_match((rure_set *)prog_.get(), 
                                             (const uint8_t *)pat_str, length, 0);
           return result;
@@ -165,49 +164,31 @@ namespace re2
         }
         break;
       }
-
       case RE2::ANCHOR_BOTH:
       {
-        if(v == NULL)
+        bool matches[elem_.size()];
+        bool result = rure_set_matches((rure_set *)prog_.get(), 
+                                          (const uint8_t *)pat_str, length, 0, matches);
+        if(!result) return false;
+        if(v != NULL) v->clear();
+        for(size_t i = 0; i < elem_.size(); i++)
         {
-          bool matches[elem_.size()];
-          bool result = rure_set_matches((rure_set *)prog_.get(), 
-                                            (const uint8_t *)pat_str, length, 0, matches);
-          if(!result) return false;
-          for(size_t i = 0; i < elem_.size(); i++)
+          if(matches[i])
           {
-            if(matches[i])
+            rure *re = (rure*)elem_[i].second;
+            rure_match match = {0};
+            rure_find(re, (const uint8_t *)pat_str, strlen(pat_str),
+                           0, &match);
+            if(match.start == 0 && match.end == strlen(pat_str))
             {
-              const char *pattern = elem_[i].first.c_str();
-              rure *re = rure_compile_must(pattern);
-              rure_match match = {0};
-              rure_find(re, (const uint8_t *)pat_str, strlen(pat_str),
-                             0, &match);
-              if(match.start == 0 && match.end == strlen(pat_str)) return true;
-            }
-            
+              if(v) v->push_back(i);  // v不空的情形，把索引加入到v中
+              else return true;  // v为NULL, 直接返回匹配成功的情形
+            } 
           }
-          return false;
         }
-        else
-        { 
-          v->clear();
-          bool matches[elem_.size()];
-          bool result = rure_set_matches((rure_set *)prog_.get(), 
-                                            (const uint8_t *)pat_str, length, 0, matches);
-          if(!result) return false;
-          for(size_t i = 0; i < elem_.size(); i++)
-          {
-            if(matches[i])
-            {
-              const char *pattern = elem_[i].first.c_str();
-              rure *re = rure_compile_must(pattern);
-              rure_match match = {0};
-              rure_find(re, (const uint8_t *)pat_str, strlen(pat_str),
-                             0, &match);
-              if(match.start == 0 && match.end == strlen(pat_str)) v->push_back(i);
-            }  
-          }
+        if(v == NULL) return false; // v为空的情况
+        else // v不为空的情况，若经过处理后v中存储了相关索引，则返回true，否则false
+        {
           if(v->size()) return true;
           else return false;
         }
@@ -215,27 +196,54 @@ namespace re2
       }
       case RE2::ANCHOR_START:
       {
-        if(v == NULL)
+        bool matches[elem_.size()];
+        bool result = rure_set_matches((rure_set *)prog_.get(), 
+                                          (const uint8_t *)pat_str, length, 0, matches);
+        if(!result) return false;
+        if(v != NULL) v->clear();
+        for(size_t i = 0; i < elem_.size(); i++)
         {
-          
-          bool result = rure_set_is_match((rure_set *)prog_.get(), 
-                                            (const uint8_t *)pat_str, length, 0);
-          return result;
-        }
-        else
-        { 
-          v->clear();
-          bool matches[elem_.size()];
-          bool result = rure_set_matches((rure_set *)prog_.get(), 
-                                            (const uint8_t *)pat_str, length, 0, matches);
-          if(!result) return false;
-          for(size_t i = 0; i < elem_.size(); i++)
+          if(matches[i])
           {
-            if(matches[i]) v->push_back(i);
+            rure *re = (rure*)elem_[i].second;
+            rure_match match = {0};
+            rure_find(re, (const uint8_t *)pat_str, strlen(pat_str),
+                           0, &match);
+            if(match.start == 0)
+            {
+              if(v) v->push_back(i);  // v不空的情形，把索引加入到v中
+              else return true;  // v为NULL, 直接返回匹配成功的情形
+            } 
           }
-          return true;
+        }
+        if(v == NULL) return false; // v为空的情况
+        else // v不为空的情况，若经过处理后v中存储了相关索引，则返回true，否则false
+        {
+          if(v->size()) return true;
+          else return false;
         }
         break;
+        // if(v == NULL)
+        // {
+          
+        //   bool result = rure_set_is_match((rure_set *)prog_.get(), 
+        //                                     (const uint8_t *)pat_str, length, 0);
+        //   return result;
+        // }
+        // else
+        // { 
+        //   v->clear();
+        //   bool matches[elem_.size()];
+        //   bool result = rure_set_matches((rure_set *)prog_.get(), 
+        //                                     (const uint8_t *)pat_str, length, 0, matches);
+        //   if(!result) return false;
+        //   for(size_t i = 0; i < elem_.size(); i++)
+        //   {
+        //     if(matches[i]) v->push_back(i);
+        //   }
+        //   return true;
+        // }
+        // break;
       }
     }
     return true;
diff --git a/re2/testing/set_test.cc b/re2/testing/set_test.cc
index b03c96712ce1e63fcb691ccae80b6bdf6a5fe7f7..a7feb4c7bb928596f39fed29ef7fc134b573441f 100644
--- a/re2/testing/set_test.cc
+++ b/re2/testing/set_test.cc
@@ -51,21 +51,16 @@ TEST(Set, AnchorStart) {
 
   ASSERT_EQ(s.Match("foobar", NULL), true);
   ASSERT_EQ(s.Match("fooba", NULL), true);
-  ASSERT_EQ(s.Match("oobar", NULL), true);
+  ASSERT_EQ(s.Match("oobar", NULL), false);
 
   std::vector<int> v;
   ASSERT_EQ(s.Match("foobar", &v), true);
-  ASSERT_EQ(v.size(), 2);
-  ASSERT_EQ(v[0], 0);
-  ASSERT_EQ(v[1], 1);
-
-  ASSERT_EQ(s.Match("fooba", &v), true);
   ASSERT_EQ(v.size(), 1);
   ASSERT_EQ(v[0], 0);
 
-  ASSERT_EQ(s.Match("oobar", &v), true);
-  ASSERT_EQ(v.size(), 1);
-  ASSERT_EQ(v[0], 1);
+  ASSERT_EQ(s.Match("oobar", &v), false);
+  ASSERT_EQ(v.size(), 0);
+
 }
 
 TEST(Set, UnanchoredFactored) {