LeetCode, GeeksForGeeks Problem of the day solution

class Solution { public: int garbageCollection(vector& garbage, vector& travel) { int lastg=0, lastm=0, lastp=0, total=0; for(int i=1; i

class Solution{ public: int sumK(Node *root,int k) { unordered_map f; f[0] = 1; long long ans = 0; const long long mod = 1e9 + 7; function dfs = [&](Node * node, int sum) { if(node == nullptr) return 0; sum += node -> data; if(f.find(sum - k) != f.end()) ans = (ans + f[sum - k]) % mod; ++f[sum]; dfs(node -> left, sum); dfs(node -> right, sum); --f[sum]; if(f[sum] == 0) f.erase(sum); }; dfs(root, 0); return ans; } };

class Solution { public: int reductionOperations(vector<int>& nums) { priority_queue<pair<int,int>> pq; map<int,int> mp; int answer = 0; for(int i = 0; i < nums.size(); i++){ mp[nums[i]]++; } for(auto data : mp){ pq.push(make_pair(data.first, data.second)); } int current = pq.top().second; while(pq.size() > 1){ pair<int,int> right = pq.top(); pq.pop(); pair<int,int> left = pq.top(); if(right.first != left.first){ answer += current; current += left.second; } } return answer; } };

class Solution { public: Node* findIntersection(Node* head1, Node* head2) { Node* temp=new Node(-1); Node* sum=temp; while(head1 && head2) { if(head1->data==head2->data) { sum->next=new Node(head2->data); sum=sum->next; head1=head1->next; head2=head2->next; }else if(head1->data>head2->data){ head2=head2->next; }else{ head1=head1->next; } } return temp->next; } };

class Solution { public: int maxFrequency(vector& nums, int k) { sort(nums.begin(), nums.end()); int l=nums.size()-1, h = l; int sum = 0, res = 0; while(h>=0){ sum += nums[l]-nums[h]; while(sum > k){ int x = nums[l]-nums[l-1]; l--; sum -= x*(l-h+1); } res = max(res, (l-h+1)); h--; } return res; } };

class Solution { public: Node* reverseDLL(Node * head) { if(head == NULL || head->next == NULL) return head; Node* ntemp = head->prev; Node* ptemp = head; while(head!=NULL){ ptemp = head; head = head->next; ptemp->next = ntemp; ptemp->prev = head; if(ntemp) ntemp->prev = ptemp; ntemp = ptemp; } return ptemp; } };

class Solution { public: int minPairSum(vector& nums) { sort(nums.begin(), nums.end()); int n = nums.size(), ans=0; for (int i = 0; i < n / 2; i++) { if (i < n - i - 1) { int a = nums[i] + nums[n - i - 1]; ans = max(ans, a); } } return ans; } };

class Solution { pair solve(Node* root) { if(root -> left == NULL and root -> right == NULL) return {root, root}; if(root -> left == NULL) { pair right = solve(root -> right); root -> right = right.first; right.first -> left = root; return {root, right.second}; } if(root -> right == NULL) { pair left = solve(root -> left); left.second -> right = root; root -> left = left.second; return {left.first, root}; } pair left = solve(root -> left); pair right = solve(root -> right); left.second -> right = root; root -> left = left.second; root -> right = right.first; right.first -> left = root; return {left.first, right.second}; } public: //Function to convert binary tree into circular doubly linked list. Node *bTreeToCList(Node *root) { //add code here. if(root == NULL) return NULL; pair res = solve(root); res.first -> left = res.second; res.second -> right = res.first; return res.first; } };

class Solution { public: string findDifferentBinaryString(vector& nums) { string ans=""; int n=nums[0].size(); int p=0; for(auto i:nums) { if(i[p]=='0') ans+="1"; else ans+="0"; p++; } return ans; } };

class Solution { public: void dfs(int k , string prev , unordered_set &seen , vector &edges){ for(int i=0 ; i seen; string startingNode = string(n-1,'0'); vector edges; dfs(k,startingNode,seen,edges); string ret; int l = pow(k,n); for(int i=0 ; i< l ; i++){ ret+=(edges[i]+'0'); } ret+=startingNode; return ret; } };