code = input()
n = len(code)
p=0
stake=[]
ret=[]

t="0"
def decode(tp):
    i=tp[0]
    i=int(i)
    j=tp[1:]
    all = i* j
    all="".join(all)
    return all
while p < n:
    if(code[p]!="]"):
        stake.append(code[p])
        p+=1
    elif(code[p]=="]"):
        temp = []
        while(stake[-1]!="["):
            t=stake.pop()
            temp.append(t)
        stake.pop()
        temp.reverse()
        dc = decode(temp)
        stake.append(dc)
        p+=1

ret_final=''.join(stake)
print(ret_final)