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