Câu 1:
program ct;
uses crt;
var i,S:integer;
begin
clrscr;
S:=0; i:=0;
while i<1000 do
begin
S:=S+i;
i:=i+2;
end;
writeln('tong cac so chan la:',S);
readln
end.
Câu 2:
program ct;
uses crt;
var S,i:integer;
begin
clrscr;
S:=0;
for i:=1 to 1000 do
if (i mod 2=0) then S:=S+i;
writeln('tong cac so chan la:',S);
readln
end.