1. program TIn_hoc;

uses crt;

var i,n:integer;

begin

clrscr;

writeln('Nhap n:');readln(n);

writeln('Cac so le tu 0 den ',n,' la:');

for i:= 0 to n do if i mod 2 = 1 then write(i,'  ');

readln;

end.

2.

program Tin_hoc;

uses crt;

var i,n:integer;

     s:string;

begin

clrscr;

writeln('Nhap xau S co do dai toi da la 25:');readln(s);

while length(s) >25 do 

begin writeln('Nhap lai:');

readln(s) end;

n:=0;

for i := 1 to length(s) do if s[i] = '0' then inc(n);

writeln('Xau S co ',n,' chu so 0:');

readln;

end.

Bài 1 :

uses crt;

var k, N : integer;

begin

clrscr;

write('Nhap so N : '); readln(N);

for k := 0 to N do

if k mod 2 <> 0 then write(k,'  ');

readln

end.

Bài 2 :

uses crt;

var S : string; d, i : integer;

begin

clrscr;

write('Nhap xau S : '); readln(S);

while length(S) > 25 do

begin

write('Nhap lai xau S : ');

readln(S);

end;

d := 0;

for i := 1 to length(S) do

if s[i] = '0' then d := d + 1;

write('Xau S co ', d ,' so 0');

readln

end.