BT1:
program Tin_hoc;
uses crt;
var i,tong,n:integer;
begin
clrscr;
write('Nhap n: ');readln(n);
tong:=0;
for i := 1 to n do tong:= tong + i;
writeln('Tong = ',tong);
readln;
end.
BT2:
program Tin_hoc;
uses crt;
var i,n,tong:integer;
a: array [1..100000] of integer;
begin
clrscr;
write('Nhap n: ');readln(n);
tong:=0;
writeln('Nhap ',n,' phan tu:');
for i:= 1 to n do
begin
write('a[',i,'}: ');
readln(a[i]);
tong:= tong+a[i]
end;
writeln('Tong cua ',n,' phan tu la: ',tong);
readln;
end.
