while True:
try:
a, b, c = map(int, input().split())
if a + b > c and a + c > b and b + c > a:
if a == b == c:
print("Equilateral triangle!")
if a == b != c or b == c != a or a == c != b:
print("Isosceles triangle!")
if a != b != c and b != c and a != c and a != b:
print("Ordinary triangle!")
else:
print("Not a triangle!")
except:
break