# Uses python3
def getNumOfCoins(m):
    # coins with denominations of 1, 5, and 10
    coinCount = 0
    remainder = 0
    if m / 10 == 0 & m % 10 == 0:
        return m / 10
    coinCount = coinCount + int(m / 10)
    remainder = m % 10
    if remainder >= 5:
        return coinCount + 1 + remainder - 5
    else:
        return coinCount + remainder


m = int(input())
print(getNumOfCoins(m))