try:
    score = input("Enter Score: ")
    s = float(score)
    if s>=0.0 and s<0.6:
        print('F')
    elif s>=0.6 and s<0.7:
        print('D')
    elif s>=0.7 and s<0.8:
        print('C')
    elif s>=0.8 and s<0.9:
        print('B')
    elif s>=0.9 and s<=1.0:
        print('A')
    else:
        print("Error! Score doesnot lie in the range")
except:
	print('Please Enter a number between 0.0 and 1.0')
