câu 2:
program tong;
uses crt;
var i,n,s:integer;
begin
clrscr;
write('nhap n:=');readln(n);
s:=0;
for i:=1 to n do s:=s+i;
writeln('tong la:',s);
readln
end.
CHƯƠNG TRÌNH TÍNH TÍCH
program tich
uses crt;
var i,n,s:integer;
begin
clrscr;
write('nhap n:=');readln(n);
s:=1;
for i:=1 to n do s:=s*i;
writeln('tich la:',s);
readln
end.