x = input()
if "." not in x:
    x_int = x
else:
    x = x.split(".")
    x_float = int(str(x[1])[0])
    x_int = int(x[0])
    if x_float >= 5:
        x_int = x_int + 1
    else:
        x_int = x_int

print(x_int)