Program HOC24;

var i,n: integer;

s: longint;

begin

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

s:=0;

for i:=1 to n do if i mod 2=0 then s:=s+i;

write('S = ',s);

readln

end.

pascal

program sum_of_evens;

var
  i, n, sum: integer;

begin
  write('Enter a positive integer: ');
  readln(n);
  
  sum := 0;
  
  for i := 2 to n step 2 do
  begin
    sum := sum + i;
  end;
  
  writeln('The sum of even numbers from 2 to ', n, ' is ', sum);
end.

Bài 1:program sothuc;

uses crt;

var a:array[1..10] of real;s,i,j:real;

begin

s:=0;

for i:=1 to 10 do begin writeln('A[',i,']=');readln(a[i]); end;

for i:=1 to 10 do if a[i]<0 then

for j:=1 to 10 do

begin a[j]:=sqr(a[i]); s:=s+a[j]; end;

writeln('tong binh phuong cac so am la: ',s:2:2); readln;

end. (Khi nào mình kiểm tra chạy lại trên phần mềm rồi sửa lại nếu sai nhé)

Bài 2: 

program soduong;

uses crt;

var a:array[1..100] of integer;s,i,n:integer;

begin

clrscr;

writeln('nhap do dai cua day');readln(n);

for i:=1 to n do begin

writeln('a[',i,']=');readln(a[i]);

if a[i] mod 2 = 0 then s:=s+a[i] end;

writeln('tong so duong trong day la',s:2:0);readln

end.

Bài 3: các số dương mà là số lẻ là sao thế bạn????

Câu 1:

Program HOC24;

var i,p: integer;

t: longint;

begin

write('Nhap P: '); readln(p);

t:=0;

for i:=1 to p do if i mod 2<>0 then t:=t+i;

write('Tong cac so le la: ',t);

readln

end.

Câu 2:

Program HOC24;

var i,n: integer;

t: longint;

begin

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

t:=0;

for i:=1 to n do if i mod 2=0 then t:=t+i;

write('Tong cac so chan la: ',t);

readln

end.

Câu 3:

Program HOC24;

var i,t,n: integer;

begin

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

t:=0;

for i:=1 to n do if n mod i=0 then t:=t+i;

write('Tong cac uoc cua ',n,' la: ',t);

readln

end.

1. Uses crt;

var n,i: integer;

begin clrscr;

readln(n);

for i:=1 to n do write(i:3);

readln;

end.

2. Uses crt;

var n,i: integer;

begin clrscr;

readln(n);

for i:=1 to n do if(i mod 2 = 0) then write(i:3);

readln;

end.

1. Uses crt;

var n,i: integer;

begin clrscr;

readln(n);

for i:=1 to n do write(i:3);

readln;

end.

2. Uses crt;

var n,i: integer;

begin clrscr;

readln(n);

for i:=1 to n do if(i mod 2 = 0) then write(i:3);

readln;

end.

1.

program InDaySoTuNhien;
var n, i: integer;
begin
   write('Nhap so nguyen duong n: ');
   readln(n);

   writeln('Day so tu 1 den ', n, ' la:');
   for i := 1 to n do
      write(i, ' ');
end.

2.

program InSoChan;
var
   n, i: integer;
begin
   write('Nhap so nguyen n: ');
   readln(n);

   writeln('Cac so nguyen chan trong khoang tu 1 den ', n, ' la:');
   for i := 1 to n do
   begin
      if i mod 2 = 0 then
         write(i, ' ');
   end;
end.

program bai1;

uses crt;

var a,b,c,s: real;

begin

clrscr;

write('nhap so thu nhat ='); readln(a);

write('nhap so thu hai ='); readln(b);

write('nhap so thu ba ='); readln(c);

s:=a+b+c;

writeln('tong ba so a,b,c =',s:4:2);

readln;

end.

program bai1;

uses crt;

var n: integer;

begin

clrscr;

write('nhap so n ='); readln(n);

if n mod 2 = 0 then

writeln('la so chan ') else

writeln('la so le ');

readln;

end.

bài 3 :

B1: S <- 0 ; i<-0;

B2: i<- i+1;

B3: Nếu i <= 100 thì S:=S+i; Và quay lại B2.TRong trường hợp ngược lại thông bào kết quả rồi kết thúc thuật toán.

var a:array[1..99] of integer;

i,n:integer;

s:longint;

begin

write('n = ');readln(n);

for i:=1 to n do

begin

write('Nhap so thu ',i,' = ');readln(a[i]);

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

end;

writeln('Tong cac so le cua day la ',s);

write('Day dao nguoc la ');

for i:=n downto 1 do

write(a[i]:8);

readln

end.

Câu 1: 

uses crt;

var s,i:integer;

begin

clrscr;

s:=0;

for i:=1 to 10 do 

  s:=s+i;

writeln('Tong cua 10 so tu nhien dau tien la: ',s);

readln;

end.

Câu 2: 

uses crt;

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

i,n,dem:integer;

begin

clrscr;

write('Nhap n='); readln(n);

for i:=1 to n do 

  begin

write('A[',i,']='); readln(a[i]);

end;

dem:=0;

for i:=1 to n do

if a[i]>0 then inc(dem);

writeln('So luong phan tu duong la: ',dem);

readln;

end.

Câu 3: 

uses crt;

var i,j:integer;

begin

clrscr;

for i:=1 to 9 do 

  begin

      writeln('Bang nhan ',i,' la: ');

for j:=1 to 10 do 

  writeln(i,'*',j,'=',i*j);

delay(200);

end;

readln;

end.

program Tinh_Tong;

var n, s, i: integer;

begin
  write('Nhap vao so nguyen duong n: ');
  readln(n);
  s := 0;
  i := 1;
  while i <= n do
  begin
    s := s + i;
    i := i + 1;
  end;
  writeln('Tong cua ', n, ' so tu nhien dau tien la: ', s);
  end.