program ho_tro;
uses crt;
var s,i: real;
begin
clrscr;
s:=1;
for i:=1 to 105 do
s:=s+i;
writeln(' tong cac so tu 1 den 105 =',s);
readln
end.
uses crt;
var i,s:longint;
begin
clrscr;
s:=0;
for i:=0 to 104 do
s:=s+i;
writeln('tong 105 so tu nhien dau tien la:',s);
readln;
end.
bn tự khai báo nha!
begin
clrscr;
s:=0;
for i:=1 to 105 do
s:=s+i;
writeln('tong s la:',s);
readln
end.