def dvo(dov):
    print(end=f"{dov}")
def VM(code):
    A = 0
    J = 0
    loop = []
    Julia = code.split(" ")
    k = []
    Save = [0]*(2**16)
    while A < len(Julia):
        if Julia[A] == "□□□□□□□□":
            k.append(0)
        elif Julia[A] == "□□□□□□□■":
            k[-1] += int(Julia[A+1])
        elif Julia[A] == "□□□□□□■□":
            Save[int(Julia[A+1])] = k.pop()
        elif Julia[A] == "[":
            loop.append([0,int(Julia[A+1]),A])
        elif Julia[A] == "]":
            if Save[loop[-1][1]] > 0:
                A = Save[loop[-1][-1]]
            else:
                loop.pop()
        elif Julia[A] == "□□□□□■□■":
            k[-1]=Save[int(Julia[A+1])]
        elif Julia[A] == "□□□□□■■□":
            dvo(k[-1])
        A += 1
VM("□□□□□□□□ □□□□□□□■ 21 □□□□□□■□ 5 □□□□□□□□ □□□□□■□■ 5 □□□□□■■□ ")