The question is you are given an array A of N integers N<=10^5 and q queries, q <= 10^5.
The are for types of query operation.
0 x y --> find the sum in the range x to y , 0 based index.
1 x --> Append element with value x to the end of array.
2 x ---> Delete element at index x, all the elements from x+1 to n-1 index comes forwards.
3 x y --> Change A[x] to y.
You have to return answer for all sum queries, that is query 1.
How to solve such problem.