King Graff, the ruler of the land of Feerie, is going on a trip through his realm! He would like to give his people a chance to see their great king amongst them, almost as if he too were a petty commoner with no future.
Feerie consists of
towns (numbered
),
and
roads. The
th road runs from town
to a different town
(and can only be travelled in that
one direction), and takes
minutes to
traverse. No pair of towns is directly connected by more than one road
in the same direction. King Graff will start his trip at town
, and
would like to end at a different town
. Furthermore, since he has
better things to do, he would like to complete it in at most
minutes.
However, Graff does not like to go long without being worshipped, and
the only proper place to do this is in a shrine built to him.
distinct towns contain such shrines - the
th shrine
is in town
. He would like to minimize the longest continuous
stretch of time spent during the trip without passing through any
shrines. As the royal computer scientist, your job is to determine the
length of this stretch, or break the news to your king that the trip
cannot be completed in time. Note that the trip may be impossible to
complete in any amount of time, if town
is not reachable from town
by any path of connected roads.
Input Specification
Line 1: 5 integers, ,
,
,
, and
Next lines: 3 integers,
,
, and
, for
Next line: 1 integer,
Next lines: 1 integer,
, for
Output Specification
Line 1: 1 integer - the minimum value for the longest continuous stretch
of travel time spent away from shrines (in minutes), or -1
if the trip
cannot be completed in at most minutes
Sample Input
5 7 2 3 7
2 3 5
3 2 1
2 1 4
1 3 3
2 4 3
4 5 2
5 3 3
3
1
4
5
Sample Output
4
Explanation of Sample
The map of Feerie is illustrated below:
The optimal route goes through towns , taking 7 minutes with at
most 4 minutes spent away from any shrines. The route
is shorter
(taking 5 minutes), but has a longer continuous time away from shrines
(5). The route
has a shorter such value (3), but takes
longer than 7 minutes in total (8) and as such is not allowed.
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