n, a, b, c  = [int(i) for i in input().split()]
currentNumber = n
while a > 0 or b > 0 or c > 0:
    if a > 0 and b > 0 and c > 0:
        arr = [currentNumber // 2, (currentNumber + 1) // 2, currentNumber if currentNumber == 0 else (currentNumber - 1) // 2]
        currentNumber = min(arr)
        if arr.index(currentNumber) == 0:
            a -= 1
        elif arr.index(currentNumber) == 1:
            b -= 1
        elif arr.index(currentNumber) == 2:
            c -= 1
    elif a > 0 and b > 0:
        arr = [currentNumber // 2, (currentNumber + 1) // 2]
        currentNumber = min(arr)
        if arr.index(currentNumber) == 0:
            a -= 1
        elif arr.index(currentNumber) == 1:
            b -= 1
    elif a > 0 and c > 0:
        arr = [currentNumber // 2, currentNumber if currentNumber == 0 else (currentNumber - 1) // 2]
        currentNumber = min(arr)
        if arr.index(currentNumber) == 0:
            a -= 1
        elif arr.index(currentNumber) == 1:
            c -= 1
    elif b > 0 and c > 0:
        arr = [(currentNumber + 1) // 2, currentNumber if currentNumber == 0 else (currentNumber - 1) // 2]
        currentNumber = min(arr)
        if arr.index(currentNumber) == 0:
            b -= 1
        elif arr.index(currentNumber) == 1:
            c -= 1
    elif a > 0:
        currentNumber = currentNumber // 2
        a -= 1
    elif b > 0:
        currentNumber = (currentNumber + 1) // 2
        b -= 1
    elif c > 0:
        currentNumber = currentNumber if currentNumber == 0 else (currentNumber - 1) // 2
        c -= 1
print(currentNumber)