Valid triangle in one line

gistfile1.rb

# Triangle side lengths
# Write a method valid_triangle? which takes as its input three non-negative numbers. 
#It should return true if the three numbers could form the side lengths of a triangle and false otherwise.

# The arguments don't correspond to specific sides. 
# Don't worry about handling negative inputs — garbage in, garbage out.

# For example,

# valid_triangle?(0,0,0) # => false, because a triangle can't have 0-length sides
# valid_triangle?(1,1,1) # => true, an equilateral triangle
# valid_triangle?(3,4,5) # => true, a right triangle
# valid_triangle?(4,3,5) # => true, the same right triangle
# valid_triangle?(5,3,4) # => true, the same right triangle
# valid_triangle?(10, 10, 100) #=> false, no such triangle exists

def valid_triangle?(a, b, c)
 !(a+b+c <= 0 || a+b < c || a+c < b || b+c < a)
end