// PascalABC.NET
begin
var m := ReadSeqIntegerWhile(p -> p <> 0)
.Where(p -> p in 10..99)
.DefaultIfEmpty
.Average;
if m > 0 then
m.Print
else
Print('NO')
end.
// PascalABC.NET
begin
var m := ReadSeqIntegerWhile(p -> p <> 0)
.Where(p -> p in 10..99)
.DefaultIfEmpty
.Average;
if m > 0 then
m.Print
else
Print('NO')
end.