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