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its most probably a bug in you program. are you by chance reading integer coordinates?

regards
-j

i verified that there are ambigous inputs. this is part of my code which gives AC whithout the check and RE whith the for loop to check for ambigous paths. (the for loop checks, while doing the output, if there is an edge not going to the parent wich would give the same distance to the start node ...

the distance to the tree (that whats i meant with min of the distances)

-justus

what is the meaning of maximum safe travel distance?
if the distance from origin to right tangent is smaller than the distance
from origin to left,which should I output?

its the max length you can go from your house in a straight line without hitting the radiation no matter which direction you ...

wenzhi cai wrote:Can anyone tell me why the sample output should be 2.400
with input 5 5 1 12 12

in this case the distance from the house to left tangent (tangent from origin to tree) and to right tangent equals 2.4 and is smaller than the distance to the tree.

-justus

ok i found out, what the problem was.

in my first version the compiler let the values in the fpu registers (so with 80bits) in the other version i stored the values in doubles and so lost the precision. if i use long doubles i get AC for this version to.

so everybody might try to use long doubles ...

hi!

i've solved that problem, but it's really strange. i got a short solution without trigonometric functions. only '*', '/' and sqrt. but if i just store some values (as distance from origin to treecenter) in a variable, instead of recalculating every time it's used, i get WA.

i can't even think ...