$N$ plates are arranged in a straight line from left to right. Let us call the $i$\-th plate from the left $(1\le i\le N)$ plate $i$. Initially, all plates are placed face-up, and no plates have takoyaki (octopus dumplings) on them.
Process a total of $Q$ queries of the following three types:
* Type $1$: You are given integers $L,R,X$. For $i=L,L+1,\ldots,R$, if plate $i$ is placed face-up, place $X$ takoyaki on plate $i$.
* Type $2$: You are given integers $L,R$. For $i=L,L+1,\ldots,R$, if there is at least one takoyaki on plate $i$, eat all the takoyaki on plate $i$. Flip plate $i$ (if the plate is placed face-up, place it face-down; otherwise, place it face-up).
* Type $3$: You are given integers $L,R$. Print the maximum number of takoyaki on one plate among plates $L,$ $L+1,\ldots,$ $R$.
## Constraints
* $1\le N\le2\times10 ^ 5$
* $1\le Q\le2\times10 ^ 5$
* In all queries, $1\le L\le R\le N$.
* In type $1$ queries, $1\le X\le10 ^ 9$.
* There is at least one type $3$ query.
* All input values are integers.
## Input
The input is given from Standard Input in the following format:
$N$ $Q$
$\mathrm{query} _ 1$
$\mathrm{query} _ 2$
$\vdots$
$\mathrm{query} _ Q$
Here, $\mathrm{query} _ i$ represents the $i$\-th $(1\le i\le Q)$ query and is given in one of the following formats:
$t$ $L$ $R$ $X$
$t$ $L$ $R$
These indicate that the $i$\-th query is of type $t$ and the given integers are $L,R,X$ or $L,R$. Type $1$ queries are given in the former format, and other queries are given in the latter format.
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