Soon the main event of the evening is closing in, the
Striker-Count tournament that KFFÍ intends to watch together.
However a minor problem came up, the video is being picked up
via satellite and the satellite dish on the roof has lost its
aim, so it needs to be adjusted. Eyleifur, a hero as always,
offers to climb up onto the roof and take care of things. When
he gets to the top of the ladder to the roof he notices that
the roof is not only quite uneven but quite wet and thus
slippery. Due to how slippery it is, Eyleifur will only take a
step from one tile on the roof to another if the height
difference isn’t too great. When Eyleifur finishes assessing
the situation he jots down a sketch of the roof. Since turning
on slippery surfaces can be a bit tricky Eyleifur will only
move horizontally or vertically along the roof (seen from
above).
Input
The first line of the input contains two integers
satisfying
. is
the maximum height Eyleifur will scale upwards in a single step
and is the maximum
height Eyleifur is the maximum height Eyleifur will scale
downwards in a single step. The next line contains two integers
satisfying
.
They will also satisfy . Next the input will contain lines each containing integers satisfying . The
numbers give
the height map Eyleifur made of the roof. is always equal to
and is where Eyleifur
climbs up onto the roof and begins his walk towards the
satellite dish. The last line of the input contains two
integers
satisfying and which give the location of the satellite dish.
Output
Print ‘Kvoldinu er bjargad!’ if Eyleifur can make it to the
satellite dish and back to the ladder. If there is no way for
Eyleifur to get to the satellite dish and back, print ‘Nu er
Eyleifur i bobba!’.
| Sample Input 1 |
Sample Output 1 |
1 2
3 3
0 2 6
1 3 5
2 3 4
3 3
|
Kvoldinu er bjargad!
|
| Sample Input 2 |
Sample Output 2 |
1 0
2 3
0 5 4
1 2 3
1 2
|
Nu er Eyleifur i bobba!
|
