x, a, b = list(map(int,input().split()))

if b-a <= x and b-a <= 0:

  print('delicious')

elif b-a <= x:

  print('safe')

else:

  print('dangerous')

  
x,a,b = list(map(int,input().split()))

if -a+b <= 0:

    print('delicious')

elif -a+b <= x:

    print('safe')

else:

    print('dangerous')
x, a, b = list(map(int, input().split()))
if b - a <= x and b - a <= 0:
    print("delicious")
elif b - a <= x:
    print("safe")
else:
    print("dangerous")

x, a, b = list(map(int, input().split()))
if -a + b <= 0:
    print("delicious")
elif -a + b <= x:
    print("safe")
else:
    print("dangerous")

-if b - a <= x and b - a <= 0: +if -a + b <= 0: -elif b - a <= x: +elif -a + b <= x: