Program HOC24;
var i,n,t: integer;
begin
n:=1; t:=0;
while t<=20 do
begin
t:=t+n;
n:=n+1;
end;
writeln('Tong la: ',t);
readln
end.
uses crt;
var i,n,t:integer;
begin
clrscr;
t:=0;
for i:=1 to 20 do
t:=t+i;
if t>20 then
begin
writeln(t);
break;
end;
readln;
end.