while 1: 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!') elif (a == b) or (a == c) or (b == c): print('Isosceles triangle!') else: print('Ordinary triangle!') else: print('Not a triangle!') except: break