Uri 1120

while True:
    d, n = map(str, input().split(' '))

    if d == '0' and n == '0':
        break

    n = list(n)
    i = 0
    while i < len(n):
        if d == n[i]:
            n.pop(i)

        else:
            i += 1

    if len(n) == 0:
        print(0)

    else:
        print(int(''.join(n)))