Program P1;
var
n, k, i, r: integer;
begin
writeln('Vvedite N:');
readln(n);
writeln('Vvedite K:');
readln(k);
r := 0;
for i := 1 to n - 1 do
if i mod k = 0 then
r := r + i;
writeln(r);
readln;
end.
Program P1;
var
n, k, i, r: integer;
begin
writeln('Vvedite N:');
readln(n);
writeln('Vvedite K:');
readln(k);
r := 0;
for i := 1 to n - 1 do
if i mod k = 0 then
r := r + i;
writeln(r);
readln;
end.