


# 백준 #30676 (이 별은 무슨 색일까)
# Wavelength : 파장 입력
Wavelength = int(input())
if 620 <= Wavelength <= 780 :
print("Red")
elif 590 <= Wavelength < 620 :
print("Orange")
elif 570 <= Wavelength < 590 :
print("Yellow")
elif 495 <= Wavelength < 570 :
print("Green")
elif 450 <= Wavelength < 495 :
print("Blue")
elif 425 <= Wavelength < 450 :
print("Indigo")
elif 380 <= Wavelength < 425 :
print("Violet")