#Group anagram #Map Method 1 map<string, vector<string>>mp; Method 2->using hash map as a key of map 1 st time. map<std::array<int,256>,vector<string>>mp; Making function of hash map first time .

Q 8->atoi-> String to integer. Learned use of isdigit(s[i]). To determine whether the given character is digit or not

Q-> 12 Integer to Roman Here I learn that we use push_back to insert a single character to an empty string or a vector for ans To push a string inside an empty string we use append function Like ans.append(Roman symbol [i]); Or ans+=RomanSymbol[i] ' ' store character " " Str

Q 51 N-Queens Use of map. #Backtracking Putting a string into a tempvector and consequently putting that temporary vector into a 2D string vector. See how efficiently and clearly isSafe() function is used. Unordered_map<int,bool>mp is used Int -> represent the index of board .

Q->415 Add Strings digit= csum/10; ans carry=csum%10; n1=(p1>=0 ? num[p1] : '0')-'0';

Q->44 Wildcard Matching Only used recursion,so time limit exceeded occuring .

Q-1155. Well known question of DP .

Rat in a maze problem 1 #gfg Be aware about visited matrix,inialise all the cell of visited matrix by false. 3 conditions to move forward 1-> check boundary conditions 2->check visited condition 3->maze[0][0]==1 or 0

Q-22 Generate Parenthesis #recursion and Backtracking

Q->77 COMBINATIONS new concept of recursion tree be careful about value of start and backtracking.

Airbnb site. #WebDevelopment #shradhakhapra #frontened #backend

Q->79 Word Search similar to rat in a maze, be careful that in every function call we have return true, i was making mistake in this many times. 3rd boundary condition is different from rat in maze. if(word[ks]!=board[newx][newy]) return false;

Q->52 N-Queens II-leetcode even no any board vector required.

Q->47 Permutation II good use of set data structure. learned how to iterate on a set.

Q->876 find middle node of linked list if(fast==NULL || fast->next==NULL) return slow; fast==NULL->this condition is useful when the length of linkedlist is even. fast->next==NULL->when length is odd.

Q->243 Palindrome Linked-List 1->solve func. is finding the middle of linked list (either even / odd len). ex=> 1->2->3->2->1 0/p=>3->2->1 reverse function reverses this 3->2->1 o/p=>1->2->3 similarly for even length. at last comparing mid ke pahle wali string and reverse wali

Q->141 Linked List Cycle map is creating between adress of node(pointer) and its occurence(frequency). sir has made mapping of pointer and bool. I have mapped pointer to its occurence. optimized solution by mouse and rabbit (fast and slow) technique.

Q->83 Remove Duplicates from Sorted Linked List. Implemented without taking any help.

#gfg Sort a linked list of 0s, 1s and 2s. Given the head of a linked list where nodes can contain values 0s, 1s, and 2s only

#loveBabbar Add 1 to a Linked List Number learnt a new method to create a new node by inserting numerical value. if(carr!=0 && back->next==NULL) { Node* newnode = new Node(carr); back->next = newnode; }