Var a:array[1..4] of integer;
i,max:integer;
b:boolean;
begin
b:=false;
for i:=1 to 4 do
read(a[i]);
max:=a[1];
for i:=1 to 4 do
if (not odd(a[i])) and (a[i]>=max) then begin
max:=a[i];
b:=true;
end;
if b then write('',max) else write('not found');
end.

Var
    a: array[1..4] of integer;
    i, max: integer;

begin
    for i := 1 to 4 do
        readln(a[i]);
    
    max := a[1];
    for i := 1 to 4 do
        if (a[i] mod 2 = 0) and (a[i] >= max) then
            max := a[i];
    
    if max mod 2 = 0 then
        writeln(max)
    else
        writeln('not found');
end.