48 lines
1.1 KiB
Text
48 lines
1.1 KiB
Text
class Triangle(a, b, c) {
|
|
|
|
has (sides, perimeter, area)
|
|
|
|
method init {
|
|
sides = [a, b, c].sort
|
|
perimeter = [a, b, c].sum
|
|
var s = (perimeter / 2)
|
|
area = sqrt(s * (s - a) * (s - b) * (s - c))
|
|
}
|
|
|
|
method is_valid(a,b,c) {
|
|
var (short, middle, long) = [a, b, c].sort...;
|
|
(short + middle) > long
|
|
}
|
|
|
|
method is_heronian {
|
|
area == area.to_i
|
|
}
|
|
|
|
method <=>(other) {
|
|
[area, perimeter, sides] <=> [other.area, other.perimeter, other.sides]
|
|
}
|
|
|
|
method to_s {
|
|
"%-11s%6d%8.1f" % (sides.join('x'), perimeter, area)
|
|
}
|
|
}
|
|
|
|
var (max, area) = (200, 210)
|
|
var prim_triangles = []
|
|
|
|
for a in (1..max) {
|
|
for b in (a..max) {
|
|
for c in (b..max) {
|
|
next if (Math.gcd(a, b, c) > 1)
|
|
prim_triangles << Triangle(a, b, c) if Triangle.is_valid(a, b, c)
|
|
}
|
|
}
|
|
}
|
|
|
|
var sorted = prim_triangles.grep{.is_heronian}.sort
|
|
|
|
say "Primitive heronian triangles with sides upto #{max}: #{sorted.size}"
|
|
say "\nsides perim. area"
|
|
say sorted.first(10).join("\n")
|
|
say "\nTriangles with an area of: #{area}"
|
|
sorted.each{|tr| say tr if (tr.area == area)}
|