#include "string.h"

int main()

{

char k[110],c[1010],m[1010];

int nk,nc,fk,i,n,f;

gets(k);

gets(c);

nk=strlen(k);

nc=strlen(c);

fk=-1;

for(i=0;i<nc;i++)

{

fk++;

if(fk>=nk) fk=0;

if(k[fk]>='a' && k[fk]<='z') n=k[fk]-97+1;

if(k[fk]>='A' && k[fk]<='Z') n=k[fk]-65+1;

m[i]=c[i]-n+1;

if(!(m[i]>='a' && m[i]<='z') && (c[i]>='a' && m[i]<='z'))

m[i]+=26;

else if(!(m[i]>='A' && m[i]<='Z') && (c[i]>='A' && m[i]<='Z'))

m[i]+=26;

printf("%c",m[i]);

}

return 0;

}