program SumNumbers;

var
n, sum, i: integer;

begin
sum := 0;

writeln('Enter a positive integer:');
readln(n);

if n < 1 then
writeln('Invalid input. Please enter a positive integer.')
else
begin
for i := 1 to n do
sum := sum + i;

writeln('The sum of integers from 1 to ', n, ' is: ', sum);
end;

end.