#55464: python 簡單解
hges10914@gapp.hcc.edu.tw
(勞贖能吃嗎)
a = int(input())
b = a // 12
c = a % 12
print(b*50+c*5)
a = int(input())
b = a // 12
c = a % 12
print(b*50+c*5)