Basics
Comment - for In-line comment (means comment in same line) --> Use // for multi-line comment --> Use /* ........ */ Array - int arr[10] = {4, 5, 8} --> creates array of size 10 with first 3 elements known Access - 10[arr] or arr[10] --> both correct bcz *(10+arr) and *(arr+10) are same Pair - pair<int,string> p = {2 , "fsf"} How to access ? p.first and p.second Vector - array with dynamic memory size => continuous memory allocation How to initialize vector ? vector <double> v(10) => declares vector of size 10 with each value as 0 vector <double> v(7 , 3) => declares vector of size 7 with each value as 3 vector <double> v = {1, 3, 5, 10} => declares vector of with given values vector <double> v(st.begin(), st.end()) => declares vector from given set vector <int> v1 =v ...