Câu 1 :

uses crt;

var i, s : longint;

begin

clrscr;

s := 0;

for i := 1 to 100 do 

if i mod 2 = 0 then s := s + i;

writeln('tong = ', s);

if s mod 2 = 0 then

writeln('tong la so chan')

else writeln('tong la so le');

readln

end.

Bài 2 :

uses crt;

var a : array[1..100] of integer;

i, n, dem : integer;

begin

clrscr;

dem := 0;

write('nhap so phan tu trong mang :');readln(n);

for i := 1 to n do

begin

write('nhap phan tu thu ', i ,' : ');readln(a[i]);

if a[i] mod 2 <> 0 then dem := dem + 1;

end;

writeln('co ', dem ,' phan tu le');

readln

end.

Program BTH;
uses crt;
var a:array[1..100000] of longint;
n,i,s:longint;
begin
        clrscr;
        write('Nhap n: ');readln(n);
        For i:=1 to n do
        begin
                write('a[',i,']: ');readln(a[i]);
                If (a[i] mod 2=0) and (a[i] mod 5=0)
                then s:=s+a[i];
        end;
        writeln('Tong day so tren la: ',s);
        readln;
end.