program ct;
uses crt;
var A:array[1..1000] of integer;
i,n:integer;
begin clrscr;
writeln('Nhap so phan tu: '); readln(n);
for i:=1 to n do
begin
writeln('A[',i,']: '); readln(A[i]);
end;
for i:=1 to n do
if i mod 3=0 then write('Day chia het cho 3 la: ',A[i]);
readln;
end.
Học tốt!