import sys n = float(input()) if n>=2000: if n >=3000: if n >=4000: m = n*0.6 print(round(m, 1)) sys.exit() m = n*0.7 print(round(m, 1)) sys.exit() m = n*0.8 print(round(m, 1)) sys.exit() else: print(round(n, 1))