def execute(stringIn):
    file=open("txt.txt","r")
    listData=file.readlines()
    file.close()

    vbar=stringIn.index("|")
    Command = stringIn[0:vbar]
    stringIn=stringIn[vbar+1:]

    vbar=stringIn.index("|")
    amount=stringIn[0:vbar]
    stringIn=stringIn[vbar+1:]

    vbar=stringIn.index("|")
    account=stringIn[0:vbar]
    stringIn=stringIn[vbar+1:]
    searchString=account+"|"+stringIn+"|"
    for i in range(0,len(listData)):

        if(searchString in listData[i]):
            print(listData[i])
            balance=int(listData[i][len(searchString):])

            if(Command=="add"):
                balance+=int(amount)

            elif(Command=="sub"):
                balance-=int(amount)

            if(balance>=0):
                    listData[i]=searchString+str(balance)+"\n"
    file=open("txt.txt","w")
    file.writelines(listData)
    file.close