In Toronto, the TTC operates a commuter train network with
stations connected by
bidirectional tracks. The stations are connected such that every pair of stations are connected by travelling along a sequence of tracks. Each track takes
minute to traverse.
Union Station is the center of the network and is labelled node
. Given the city's geography, all the tracks radiate outwards from downtown from west to east. The stations are numbered in ascending order based on its distance to Union Station. Stations that are at the same distance are numbered from west to east.
To improve the efficiency of the network, the TTC is considering adding a "crosstown" line, which will consist of a series of tracks that connect adjacent nodes that are the same distance from Union Station. Each track in the line will also take
minute to traverse. To decide on the location of the line, they decide to ask
queries. In the
th query, they want to find the minimum time it takes for a commuter to travel from station
to
if the line was built at distance
. Can you write a program to answer them?
Constraints
For all subtasks:

for all 
Points Awarded |
 |
 |
2 points |
 |
 |
2 points |
 |
 |
11 points |
 |
 |
Input Specification
The first line of input contains two integers
and
.
The next
lines each contain two integers
and
, indicating a track connecting stations
and
.
The next
lines each contain three integers
,
and
.
Output Specification
For each query, output the minimum time in minutes on a separate line.
Sample Input
Copy
9 4
1 2
1 3
1 4
2 5
2 6
4 7
7 8
7 9
2 8 2
6 5 2
5 4 2
1 7 4
Sample Output
Copy
3
1
3
2
Explanation for Sample Output
Initially, the train network looks like this:
If the line was built at distance
(the added tracks are coloured red), the network would look like this:
For the first query, the passenger can travel from
in
minutes.
For the second query, station
is directly connected to station
, thus only taking
minute to travel.
For the third query, the passenger can travel from
in
minutes. Notice that the passenger can also travel from
in the same amount of time.
For the fourth query, the passenger can travel from
in
minutes. There are no stations at a distance of
so no new tracks would be added.
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