#수정 필요
#디코딩 해보기
def decode(key1,key2,n):
    n=ord(n)-ord('a')
    while(n % 26 != 0):
        n += 26
    n = n - key2
    n = n / key1
    return n
sentence_before=input()
sentence_after=''
key1=int(input())
key2=int(input())
for n in sentence_before:
    sentence_after+=decode(key1,key2,n)
print(sentence_after)