LeetCode 2015.7.26 116,108,96,94,35,80,77,74,73

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LeetCode 2015.7.26 116,108,96,94,35,80,77,74,73116 Populating Next Right Pointers in Each Node1.class Solution {public:    vector <TreeLinkNode*> next;    void connect(TreeLinkNode *root) {        depthSearch(root,0);        next.clear();    }    void depthSearch(TreeLinkNode* root,int depth) {        if (root!=NULL)        {      //      cout<<root->val<<"   "<<depth<<endl;            if (depth>=next.size())            {                next.push_back(root);            }            else            {                TreeLinkNode* p = next[depth];                p->next = root;                next[depth] = root;            }            depthSearch(root->left,depth+1);            depthSearch(root->right,depth+1);        }        return ;    }};2. 搜的解题报告class Solution {public:    void connect(TreeLinkNode *root) {        if (root == NULL) return ;        if (root->next && root->right)            root->right->next = root->next->left;        if (root->left)            root->left->next=root->right;        connect(root->left);        connect(root->right);    }};108 Convert Sorted Array to Binary Search Treeclass Solution {public:    TreeNode* sortedArrayToBST(vector<int>& nums) {        if (nums.size()==0) return NULL;        TreeNode* tmp = new TreeNode(0);        if (nums.size() == 1)        {            tmp->val = nums[0];            return tmp;        }        else        {            int mid = nums.size()/2;            tmp->val = nums[mid];            vector<int>nleft;            vector<int>nright;            nleft.clear();nright.clear();            for(int i=0;i<mid;i++)                nleft.push_back(nums[i]);            for(int i=mid+1;i<nums.size();i++)                nright.push_back(nums[i]);            tmp->left = sortedArrayToBST(nleft);            tmp->right = sortedArrayToBST(nright);        }        return tmp;    }};96 Unique Binary Search Treesclass Solution {public:    int numTrees(int n) {        vector<int> f;        f.clear();        f.resize(n+2);        f[0]=1;        f[1]=1;        f[2]=2;        if (n<=2) return f[n];        for(int i=3;i<=n;i++)        {            f[i]=0;            for(int j=0;j<i;j++)                f[i]+=f[j]*f[i-j-1];        }        return f[n];    }};94 Binary Tree Inorder Traversalclass Solution {public:    vector<int> inorderTraversal(TreeNode* root) {        vector<int> ans;        if (root == NULL) return ans;        stack<TreeNode*> s;        TreeNode* T = root;        while (T || !s.empty())        {            while (T)            {                s.push(T);                T=T->left;            }            T = s.top();            s.pop();            ans.push_back(T->val);            T=T->right;        }        return ans;    }};35 Search Insert Positionclass Solution {public:    int searchInsert(vector<int>& nums, int target) {        if (nums.size()==0) return 0;        int left = 0, right = nums.size()-1;        while (left<right)        {            int mid = left + (right-left) / 2;            if (nums[mid] == target) return mid;            if (nums[mid] > target) right = mid - 1;            else left = mid + 1;        }        if (nums[left] >= target) return left;        else return left+1;    }};80 Remove Duplicates from Sorted Array II1.class Solution {public:    int removeDuplicates(vector<int>& nums) {        map<int,int> cnt;        vector<int> ans;        map<int,int>::iterator it;        for(int i=0;i<nums.size();i++)        {            it = cnt.find(nums[i]);            if (it!=cnt.end())            {                if (it->second <2)                {                    int tmpsecond = it->second + 1;                    cnt.erase(it);                    cnt.insert(pair<int,int>(nums[i],tmpsecond));                    ans.push_back(nums[i]);                }            }            else            {                cnt.insert(pair<int,int>(nums[i],1));                ans.push_back(nums[i]);            }        }        nums.clear();        nums.resize(ans.size());        copy(ans.begin(),ans.end(),nums.begin());        return nums.size();    }};2.搜的思路class Solution {public:    int removeDuplicates(vector<int>& nums) {        if (nums.size()<3) return nums.size();        vector<int> ans;        ans.push_back(nums[0]);        ans.push_back(nums[1]);        for(int i=2;i<nums.size();i++)        {            if (nums[i]!=nums[i-2])                ans.push_back(nums[i]);        }        nums.clear();        nums.resize(ans.size());        copy(ans.begin(),ans.end(),nums.begin());        return nums.size();    }};77 Combinationsclass Solution {public:    vector<int> per;    vector< vector<int> > ans;    vector< vector<int> > combine(int n, int k) {        ans.clear();        per.resize(k);        generateCombine(n,k,1,0);        return ans;    }    void generateCombine(int n, int k, int start , int index) {        if (k==0)        {            ans.push_back(per);            return ;        }        for(int i=start;i<=n;i++)        {            per[index] = i;            generateCombine(n,k-1,i+1,index+1);        }    }};74 Search a 2D Matrix1.class Solution {public:    bool searchMatrix(vector <vector<int> >& matrix, int target) {        if (matrix.size()==0) return false;        int row = matrix.size()-1;        int col = matrix[0].size()-1;        int left = 0,right = row, r;        while (left < right)        {            int mid = left + (right - left) / 2;            if (matrix[mid][col]>=target && matrix[mid][0]<=target)                {                    r=mid;break;                }            if (matrix[mid][col]<target) left = mid + 1;            else right=mid - 1;        }        if (left >= right) r = left;        left = 0;right = col;        while (left < right)        {           int mid = left+(right-left)/2;           if (matrix[r][mid] == target) return true;           if (matrix[r][mid] > target)                right = mid - 1;           else left = mid + 1;        }        if (matrix[r][left]==target) return true;        else return false;    }};2.搜的思路class Solution {public:    bool searchMatrix(vector <vector<int> >& matrix, int target) {        int row = matrix.size(), col = matrix[0].size();        int left = 0, right = row * col - 1;        while (left <= right)        {            int mid = left +(right - left)/2;            int r = mid / col, c = mid % col;            if (matrix[r][c]==target) return true;            if (matrix[r][c] < target)                left = mid +1;            else                right = mid -1;        }        return false;    }};73 Set Matrix Zeroes1.class Solution {public:    void setZeroes(vector< vector<int> >& matrix) {        int row = matrix.size(), col = matrix[0].size();        vector<int>c,r;        int bitsize = 32;        c.resize(10);        r.resize(10);        for(int i=0;i<row;i++)            for(int j=0;j<col;j++)            {                if (matrix[i][j]==0)                {                    int tmpr = i / bitsize, tmpc = j / bitsize;                    r[tmpr] = r[tmpr] | (1<<(i % bitsize + 1));                    c[tmpc] = c[tmpc] | (1<<(j % bitsize + 1));                }            }        for(int i=0;i<row;i++)        {            int tmpr = i / bitsize;            int tmp= 1<<(i%bitsize+1);            if ((r[tmpr]&tmp) !=0)            {                for(int j=0;j<col;j++)                    matrix[i][j]=0;            }        }        for(int i=0;i<col;i++)        {            int tmpc = i / bitsize;            int tmp = 1<<(i%bitsize+1);            if ((c[tmpc]&tmp) != 0)            {                for(int j=0;j<row;j++)                    matrix[j][i]=0;            }        }        return ;    }};2. 搜的思路class Solution {public:    void setZeroes(vector< vector<int> >& matrix) {        int row = matrix.size(), col = matrix[0].size();        bool col0=false;        for(int i=0;i<row;i++)        {            if (matrix[i][0]==0) col0=true;            for(int j=1;j<col;j++)            {                if (matrix[i][j]==0)                {                    matrix[0][j]=0;                    matrix[i][0]=0;                }            }        }        for(int i=row-1;i>=0;i--)        {            for(int j=1;j<col;j++)            {                if (matrix[i][0]==0 || matrix[0][j]==0)                    matrix[i][j] = 0;            }            if (col0) matrix[i][0]=0;        }    }};
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