program tmp;
uses crt;
var
st:string;
x,x1,x2,code,code1:integer;
begin
clrscr;
readln(x);
str(x,st);
val(st[1],x1,code);
val(st[length(st)],x2,code1);
write('rez= ',(x1+x2)/2:3:1);
readkey;
end.
program tmp;
uses crt;
var
st:string;
x,x1,x2,code,code1:integer;
begin
clrscr;
readln(x);
str(x,st);
val(st[1],x1,code);
val(st[length(st)],x2,code1);
write('rez= ',(x1+x2)/2:3:1);
readkey;
end.