var s1,s2,s3,s:string; c1,c2:char; i,j,k,l,n,m,kk:longint; begin kk:=1; repeat s1:=''; readln(s); i:=0; if (s[1]='0') and (s[3]='0') and (s[5]='0') then kk:=0 else begin while s[i+1]<>' ' do begin inc(i); s1:=s1+s[i]; end; c1:=s[i+2]; c2:=s[i+4]; for i:=1 to length(s1) do if s1[i]=c1 then s1[i]:=c2; i:=1; while s1[i]='0' do inc(i); if i>length(s1) then write('0') else for j:=i to length(s1) do write(s1[j]); writeln; end; until kk=0; end.