Cow Land is a special amusement park for cows, where they roam around, eat
delicious grass, and visit different cow attractions (the roller cowster is
particularly popular).

There are a total of $N$ different attractions ($2 \leq N \leq 10^5$). Certain
pairs of attractions are connected by pathways, $N-1$ in total, in such a way
that there is a unique route consisting of various pathways between any two
attractions. Each attraction $i$ has an integer enjoyment value $e_i$, which can
change over the course of a day, since some attractions are more appealing in
the morning and others later in the afternoon.

A cow that travels from attraction $i$ to attraction $j$ gets to experience all
the attractions on the route from $i$ to $j$. Curiously, the total enjoyment
value of this entire route is given by the bitwise XOR of all the enjoyment
values along the route, including those of attractions $i$ and $j$.

Please help the cows determine the enjoyment values of the routes they plan to
use during their next trip to Cow Land.

INPUT FORMAT:
The first line of input contains $N$ and a number of queries $Q$
($1 \leq Q \leq 10^5$). The next line contains $e_1 \ldots e_N$
($0 \leq e_i \leq 10^9$). The next $N-1$ lines each describe a pathway in terms
of two integer attraction IDs $a$ and $b$ (both in the range $1 \ldots N$).
Finally, the last $Q$ lines each describe either an update to one of the $e_i$
values or a query for the enjoyment of a route. A line of the form "1 $i$ $v$"
indicates that $e_i$ should be updated to value $v$, and a line of the form "2
$i$ $j$" is a query for the enjoyment of the route connecting attractions $i$
and $j$.

In test data worth at most 50% of points, there will be no changes to the values
of the attractions.

OUTPUT FORMAT:
For each query of the form "2 $i$ $j$", print on a single line the enjoyment of
the route from $i$ to $j$.

SAMPLE INPUT:
5 5
1 2 4 8 16
1 2
1 3
3 4
3 5
2 1 5
1 1 16
2 3 5
2 1 5
2 1 3
SAMPLE OUTPUT:
21
20
4
20

Problem credits: Charles Bailey

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