A9505 | DZY Loves Colors

DZY loves colors, and he enjoys painting.

On a colorful day, DZY gets a colorful ribbon, which consists of $n$ units (they are numbered from $1$ to $n$ from left to right). The color of the $i$ -th unit of the ribbon is $i$ at first. It is colorful enough, but we still consider that the colorfulness of each unit is $0$ at first.

DZY loves painting, we know. He takes up a paintbrush with color $x$ and uses it to draw a line on the ribbon. In such a case some contiguous units are painted. Imagine that the color of unit $i$ currently is $y$ . When it is painted by this paintbrush, the color of the unit becomes $x$ , and the colorfulness of the unit increases by $|x-y|$ .

DZY wants to perform $m$ operations, each operation can be one of the following:

1. Paint all the units with numbers between $l$ and $r$ (both inclusive) with color $x$ .
2. Ask the sum of colorfulness of the units between $l$ and $r$ (both inclusive).

Can you help DZY?

The first line contains two space-separated integers $n,m (1<=n,m<=10^{5})$ .

Each of the next $m$ lines begins with a integer $type (1<=type<=2)$ , which represents the type of this operation.

If $type=1$ , there will be $3$ more integers $l,r,x (1<=l<=r<=n; 1<=x<=10^{8})$ in this line, describing an operation $1$ .

If $type=2$ , there will be $2$ more integers $l,r (1<=l<=r<=n)$ in this line, describing an operation $2$ .

For each operation $2$ , print a line containing the answer — sum of colorfulness.