DZY Loves Colors

- 有一个 $n$ 个元素组成的序列，每个元素有两个属性：颜色 $c_i$ 和权值 $w_i$。$c_i$ 初始为 $i$，$w_i$ 初始为 $0$。$m$ 次操作，操作有两种： 1. `1 l r x`：对 $i\in [l,r]$ 的所有 $i$ 进行如下操作：设第 $i$ 个元素 **原来** 的颜色为 $y$，您要把第 $i$ 个元素的颜色改为 $x$，权值 **增加** $|y-x|$。 2. `2 l r`：求 $\displaystyle\sum_{i=l}^r w_i$。 - $1\le n,m\le 10^5$，$1\le x\le 10^8$。

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.

3 3
1 1 2 4
1 2 3 5
2 1 3

8

3 4
1 1 3 4
2 1 1
2 2 2
2 3 3

3
2
1

10 6
1 1 5 3
1 2 7 9
1 10 10 11
1 3 8 12
1 1 10 3
2 1 10

129

In the first sample, the color of each unit is initially $ [1,2,3] $ , and the colorfulness is $ [0,0,0] $ . After the first operation, colors become $ [4,4,3] $ , colorfulness become $ [3,2,0] $ . After the second operation, colors become $ [4,5,5] $ , colorfulness become $ [3,3,2] $ . So the answer to the only operation of type $ 2 $ is $ 8 $ .