Program BTH;
uses crt;
var s,i,n:longint;
Begin
        clrscr;
        i:=0;
        repeat
        i:=i+1;
        write('Nhap so thu ',i,' : ');readln(n);
        If n>0 then s:=s+n;
        until n=0;
        writeln('Tong cac so lon hon 0 trong day la: ',s);
        readln;
end.

Bài 1 :

uses crt;

var n, s : integer;

begin

clrscr;

s := 0; n := -1;

while n <> 0 do

begin write('Nhap n : ');

readln(n); s := s + n; end;

write('S = ', s);

readln

end.

Bài 2 :

uses crt;

var i, min, a, b, c, uc : integer;

begin

clrscr;

write('Nhap ba so a, b, c : '); readln(a, b, c);

min := a;

if b <min then min := b;

if c < min then min := c;

for i := min downto 1 do

if (a mod min = 0) and (b mod min = 0) and (c mod min = 0)

then begin uc := i; break end;

i := min; while not ((i mod a = 0) and (i mod b = 0) and (i mod c = 0)) do

i := i + 1;

writeln('UCLN : ', uc);

writeln('BCNN : ', i);

readln

end.