commit changes to gh-pages aug 21

Author: tg123

_includes/_root/populating-next-right-pointers-in-each-node-ii/README.md

@@ -1,4 +1,30 @@
+## Improved version of [Populating Next Right Pointers in Each Node](../populating-next-right-pointers-in-each-node)
 
-## TODO 
-  * write down thinking
+This time, finding next is a bit difficult.
+`node.right.next = node.next.left` is no longer working.
 
+But parent's next is also useful, and only need to seach a little more nodes.
+
+```
+    1
+   /  \
+  2    3
+   \    \
+    4    5
+   /    / \
+  6    7   8
+```
+
+ * `6.next` = `7` = `5.left`  = `4.next.left`
+ * `4.next` = `5` = `3.right` = `2.next.right`
+
+Searching path is like
+
+ * node's parent's left
+ * node's parent's right
+ * take node's parent's next as parent and search again
+
+
+Note:
+
+`connect(right)` before `connect(left)`, because `left nodes` depend on `right nodes' next`

_includes/_root/populating-next-right-pointers-in-each-node/README.md

@@ -1,3 +1,8 @@
+## First glance
+
+It would be an easy problem if [Binary Tree Level Order Traversal](../binary-tree-level-order-traversal) works. 
+Yet, a queue is not allow because of that constant space is required.
+
 ## Recursion
 
 connecting left and right child is easy, just `node.left.next = node.right`

_includes/_root/word-break/README.md

@@ -1,4 +1,41 @@
+## All break
 
-## TODO 
-  * write down thinking
+Brute force is my favourite. However, `2 ^ n` seems a huge number.
 
+
+## Something like [Jump Game II](../jump-game-ii)
+
+That `s[0..i]` can be `break` indicates `s[i + each d in dict]` can be `break`.
+
+Make a table `P`, such that, `P[i]` means if `s[0..i]` can be `break`.
+
+```
+dict { leet, code }
+
+Table:
+
+ 0 1 2 3 4 5 6 7 8 Index
+ * l e e t c o d e
+ 1 0 0 0 1 0 0 0 1
+
+```
+
+Calculating `P[i]`
+
+```
+dict { leet, code }
+
+Table:
+
+ 0 1 2 3 4 5 6 7 8 Index
+ * l e e t c o d e
+ 1 0 0 0 1 ? ? ? ?
+           ^
+           i
+```
+  
+here if `P[i]` wants to be true, either `s[0..i]` `(leetc)` or `s[4..i]` `(c)` must be in the dict.
+
+So,
+
+`P[i] = P[0..j] && s[j..i] in dict, j = 0..i`

populating-next-right-pointers-in-each-node-ii/index.md

@@ -1,7 +1,8 @@
 ---
 layout: solution
 title: Populating Next Right Pointers in Each Node II
-date: 2014-07-23 02:42:48 +0800
+date: 2014-08-20 17:35:02 +0800
+eaten: true
 ---
 {% assign leetcode_name = {{page.path | remove: '/index.md'}}  %}
 {% assign leetcode_readme = {{leetcode_name | append: '/README.md' | prepend: '_root/' }}  %}

populating-next-right-pointers-in-each-node/index.md

@@ -1,7 +1,7 @@
 ---
 layout: solution
 title: Populating Next Right Pointers in Each Node
-date: 2014-08-12 19:19:37 +0800
+date: 2014-08-20 16:49:17 +0800
 eaten: true
 ---
 {% assign leetcode_name = {{page.path | remove: '/index.md'}}  %}

word-break/index.md

@@ -1,7 +1,8 @@
 ---
 layout: solution
 title: Word Break
-date: 2014-07-23 02:42:48 +0800
+date: 2014-08-20 19:53:59 +0800
+eaten: true
 ---
 {% assign leetcode_name = {{page.path | remove: '/index.md'}}  %}
 {% assign leetcode_readme = {{leetcode_name | append: '/README.md' | prepend: '_root/' }}  %}