# Uses python3
import sys


def getChange(money):
    denominations = [1, 3, 4]
    minNumCoins = [0] * (money + 1)
    for m in range(1, len(minNumCoins)):
        minNumCoins[m] = float('inf')
        for i in range(len(denominations)):
            if m >= denominations[i]:
                numCoins = minNumCoins[m - denominations[i]] + 1
                if numCoins < minNumCoins[m]:
                    minNumCoins[m] = numCoins
    return minNumCoins[money]


if __name__ == '__main__':
    m = int(sys.stdin.read())
    print(getChange(m))