Program Triangle2
!------------------------------------------------------------------------------
!Program: Triangle Validity and Typing
!Author: Chris Harper
!Date: 1/31/2008
!------------------------------------------------------------------------------

IMPLICIT NONE

!declarations
real :: a, b, c
logical :: triangle, equilateral, isosceles, scalene
triangle = .False.; equilateral = .False.; isosceles = .False.; scalene = .False.

!get input vars
Print *, "Triangle Validity and Typing"
Print *, "Enter 3 lengths: "
Read *, a, b, c

!test for valid triangle first - no two sides can be less than the third
if (((a + b) >= c) .AND. ((b + c) >= a) .AND. ((c + a) >= b)) then
	triangle = .True.
	if ((a == b) .OR. (b == c) .OR. (c == a)) then !two sides are equal
		if ((a == b) .AND. (b == c)) then !all sides are equal
			equilateral = .True.
		else
			isosceles = .True.
		endif
	else !no two sides are equal
		scalene = .True. 
	endif
endif

!output results
Print *, "Triangle: ", triangle
Print *, "Equilateral: ", equilateral
Print *, "Isosceles: ", isosceles
Print *, "Scalene: ", scalene
End