Uses
CRT;
Var
a,b,c,d:integer;
function maxel(k,l,m:integer):integer;
Var
max:integer;
begin
max:=k;
if l>max then max:=l;
if m>max then max:=m;
maxel:=max;
end;
begin
ClrScr;
write('= a,b,c: ');
readln(a,b,c);
write('= d: ');
readln(d);
if (a<>d) and (b<>d) and (c<>d) then
begin
writeln('=');
writeln('max(d-a,d-b,d-c):=',maxel(d-a,d-b,d-c));
end
else
begin
if a=d then writeln('a=',D)
else
writeln('a<>',D);
if b=d then writeln('b=',D)
else
writeln('b<>',D);
if c=d then writeln('c=',D)
else
writeln('c<>',D)
end;
end.