1

return "NULL" if len(input1)==0
if input2==0:
    sum=0
    for i in input1:
        if i in ['0','1','2','3','4','5','6','7','8','9']:
            sum+=int(i)
    return str(sum) if sum!=0 else "ZERO"
if input2==1:
    sum=''
    for i in input1:
        if i not in ['0','1','2','3','4','5','6','7','8','9']:
            sum+=i
    return sum if sum!='' else "ZERO"