Help me solve this problem please ->

**** **** There is an array of n elements, initially filled with zeros. You need to write a data structure that processes two types of queries: assign value v to all elements on the segment from l to r−1, find the sum on the segment from l to r−1.

Input

The first line contains two numbers n and m (1≤n, m≤100000), the size of the array and the number of operations. The following lines contain the description of the operations. The description of each operation is as follows: 1 l r v: assign value v to all elements on the segment from l to r−1 (0≤l<r≤n, 0≤v≤109). 2 l r: find the sum on the segment from l to r−1 (0≤l<r≤n).

Output

For each operation of the second type, print the corresponding value.