Merge pull request #43 from zouwx2cs/master

add 318 folder & cpp, add 427 folder & cpp

Author: yanglbme

solution/318.Maximum Product of Word Lengths/Solution.cpp

@@ -0,0 +1,16 @@
+class Solution {
+public:
+    int maxProduct(vector<string>& words) {
+        vector<int> v(words.size(), 0) ;
+        for (int i = 0; i < words.size(); ++i)
+            for (auto ch: words[i])
+                v[i] |= 1 << (ch-'a') ;
+        
+        int M = 0 ;
+        for (int i = 0; i < words.size(); ++i)
+            for (int j = i+1; j < words.size(); ++j)
+                if ((v[i] & v[j]) == 0)
+                    M = max(M, (int)words[i].size() * (int)words[j].size()) ;
+        return M ;
+    }
+};

solution/427.Construct Quad Tree/Solution.cpp

@@ -0,0 +1,74 @@
+/*
+// Definition for a QuadTree node.
+class Node {
+public:
+    bool val;
+    bool isLeaf;
+    Node* topLeft;
+    Node* topRight;
+    Node* bottomLeft;
+    Node* bottomRight;
+
+    Node() {}
+
+    Node(bool _val, bool _isLeaf, Node* _topLeft, Node* _topRight, Node* _bottomLeft, Node* _bottomRight) {
+        val = _val;
+        isLeaf = _isLeaf;
+        topLeft = _topLeft;
+        topRight = _topRight;
+        bottomLeft = _bottomLeft;
+        bottomRight = _bottomRight;
+    }
+};
+*/
+class Solution {
+public:
+    Node* construct(vector<vector<int>>& grid) {
+        return build(grid, 0, grid.size(), 0, grid.size()) ;
+    }
+    Node *build(vector<vector<int>> &g, int l, int r, int t, int b) 
+    {
+        Node *node = new Node ;
+        node->topLeft = NULL ;
+        node->topRight = NULL ;
+        node->bottomLeft = NULL ;
+        node->bottomRight = NULL ;
+        node->isLeaf = false ;
+        
+        bool tl, tr, bl, br ;
+        if (l + 1 == r)
+        {
+            node->val = g[t][l] ;
+            node->isLeaf = true ;
+            return node ;
+        }
+        
+        int vmid = (l+r)>>1 ;
+        int hmid = (t+b)>>1 ;
+        node->topLeft = build(g, l, vmid, t, hmid) ;
+        node->topRight = build(g, vmid, r, t, hmid) ;
+        node->bottomLeft = build(g, l, vmid, hmid, b) ;
+        node->bottomRight = build(g, vmid, r, hmid, b) ;
+        
+        if (node->topLeft->isLeaf && node->topRight->isLeaf && node->bottomLeft->isLeaf && node->bottomRight->isLeaf)
+        {
+            if (node->topLeft->val && node->topRight->val && node->bottomLeft->val && node->bottomRight->val
+               || !(node->topLeft->val || node->topRight->val || node->bottomLeft->val || node->bottomRight->val))
+            {
+                node->val = node->topLeft->val ;
+                node->isLeaf = true ;
+                
+                delete(node->topLeft) ;
+                delete(node->topRight) ;
+                delete(node->bottomLeft) ;
+                delete(node->bottomRight) ;
+                
+                node->topLeft = NULL ;
+                node->topRight = NULL ;
+                node->bottomLeft = NULL ;
+                node->bottomRight = NULL ;
+            }
+        }
+        return node ;
+    }
+};