From 8eebe1bc1e1cd7868070ff42417a2c14fc5598cd Mon Sep 17 00:00:00 2001
From: sarahHe <hesha@umich.edu>
Date: Thu, 8 Jan 2015 14:08:44 -0500
Subject: [PATCH 1/3] 2015.1.8 BFS + unordered_map

---
 Word Ladder.cpp | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)
 create mode 100644 Word Ladder.cpp

diff --git a/Word Ladder.cpp b/Word Ladder.cpp
new file mode 100644
index 0000000..ed1dead
--- /dev/null
+++ b/Word Ladder.cpp	
@@ -0,0 +1,33 @@
+class Solution {
+public:
+    int ladderLength(string start, string end, unordered_set<string> &dict) {
+        if (dict.empty())   return 0;
+    
+        queue<string> matched;
+        matched.push(start);
+        unordered_map<string, int>   step_map;
+        step_map[start] = 1;
+    
+        while (!matched.empty()) {
+            string str = matched.front();
+            matched.pop();
+            for (int i = 0; i < str.length(); i++) {
+                string copy_str = str;
+                for (char j = 'a'; j <= 'z'; j++) {
+                    if (copy_str[i] == j)    continue;
+                    
+                    copy_str.replace(i, 1, 1, j);
+                    if (copy_str == end)
+                        return step_map[str] + 1;
+                    
+                    if (dict.find(copy_str) != dict.end() && !step_map[copy_str]) {
+                        matched.push(copy_str);
+                        step_map[copy_str] = step_map[str] + 1;
+                    }
+                    
+                }
+            }
+        }
+        return 0;
+    }
+};

From 537576d7b605c54a75c158f96284d7fab7a8c008 Mon Sep 17 00:00:00 2001
From: sarahHe <hesha@umich.edu>
Date: Thu, 8 Jan 2015 14:09:51 -0500
Subject: [PATCH 2/3] Delete Word Ladder.cpp

---
 Word Ladder.cpp | 33 ---------------------------------
 1 file changed, 33 deletions(-)
 delete mode 100644 Word Ladder.cpp

diff --git a/Word Ladder.cpp b/Word Ladder.cpp
deleted file mode 100644
index ed1dead..0000000
--- a/Word Ladder.cpp	
+++ /dev/null
@@ -1,33 +0,0 @@
-class Solution {
-public:
-    int ladderLength(string start, string end, unordered_set<string> &dict) {
-        if (dict.empty())   return 0;
-    
-        queue<string> matched;
-        matched.push(start);
-        unordered_map<string, int>   step_map;
-        step_map[start] = 1;
-    
-        while (!matched.empty()) {
-            string str = matched.front();
-            matched.pop();
-            for (int i = 0; i < str.length(); i++) {
-                string copy_str = str;
-                for (char j = 'a'; j <= 'z'; j++) {
-                    if (copy_str[i] == j)    continue;
-                    
-                    copy_str.replace(i, 1, 1, j);
-                    if (copy_str == end)
-                        return step_map[str] + 1;
-                    
-                    if (dict.find(copy_str) != dict.end() && !step_map[copy_str]) {
-                        matched.push(copy_str);
-                        step_map[copy_str] = step_map[str] + 1;
-                    }
-                    
-                }
-            }
-        }
-        return 0;
-    }
-};

From ded538a73745265967616a8dcf3ce9d4d512e98c Mon Sep 17 00:00:00 2001
From: sarahHe <hesha@umich.edu>
Date: Mon, 16 Feb 2015 11:40:31 -0500
Subject: [PATCH 3/3] Update Remove_Duplicates_from_Sorted_List.cc

---
 Remove_Duplicates_from_Sorted_List.cc | 25 +++++++++----------------
 1 file changed, 9 insertions(+), 16 deletions(-)

diff --git a/Remove_Duplicates_from_Sorted_List.cc b/Remove_Duplicates_from_Sorted_List.cc
index 0ae691b..54020af 100644
--- a/Remove_Duplicates_from_Sorted_List.cc
+++ b/Remove_Duplicates_from_Sorted_List.cc
@@ -9,22 +9,15 @@
 class Solution {
 public:
     ListNode *deleteDuplicates(ListNode *head) {
-        // Start typing your C/C++ solution below
-        // DO NOT write int main() function
-        ListNode **pCur = &head;
-        ListNode *pPre = NULL;
-        ListNode *entry = NULL;
-        while (*pCur != NULL) {
-            entry = *pCur;
-            if (pPre != NULL && pPre->val == entry->val) {
-                *pCur = entry->next;
-                delete entry;
-                entry = NULL;
-            } else {
-                pCur = &(entry->next);
-                pPre = entry;
-            }
+        ListNode *p = head, *q;
+        while (p && p->next) {
+            q = p->next;
+            while (q && p->val == q->val) 
+                q = q->next;
+            
+            p->next = q;
+            p = q;
         }
         return head;
     }
-};
\ No newline at end of file
+};