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