Bài 1: 

uses crt;

var n,i:integer;

s:real;

begin

clrscr;

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

s:=1;

for i:=1 to n do 

 s:=s*i;

writeln(n,'!=',s:0:0);

readln;

end.

1).

program oken;

uses crt;

var n,i: integer;

      gt: qword;

begin

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

gt:=1;

for i:=1 to n do gt:=gt*i;

writeln('N!=',gt);

readln;

end.

2).

program tongcacsole;

uses crt;

var t,i:longint;

begin

clrscr;

for i:=1 to 203 do 

  if i mod 2 = 1 then t:=t+i;

write(t);

end.

3).

program tongcacsochan;

uses crt;

var t,i:longint;

begin

clrscr;

for i:=1 to 20 do 

  if i mod 2 = 0 then t:=t+i;

write(t);

end.

Program bt_3;

Uses crt;

Var Tong, n, i: integer;

Begin

 Clrscr;

 Writeln(‘nhap n=’);

 Readln (n);

 Tong:=0;

 For i:=1 to n do

 If I mod 2 = 0 then Tong:= Tong+i;

 Writeln(‘Tong la:’,Tong);

 Readln

End.

Program bt_3;

Uses crt;

Var Tong, n, i: integer;

Begin

 Clrscr;

 Writeln(‘nhap n=’);

 Readln (n);

 Tong:=0;

 For i:=1 to n do

 If I mod 2 = 1 then Tong:= Tong+i;

 Writeln(‘Tong la:’,Tong);

 Readln

End.

Program HOC24;

var i,n: integer;

S,P: longint;

begin

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

{..............................................}

readln

end.

-----------------------------------------------------------

Bạn điền vào {........................} theo từng bài nhé

a) S:=0; 

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

write('S= ',s);

b)

S:=0;

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

write('S= ',s);

c) P:=1;

for i:=1 to N do if i mod 2=0 then p:=p*i;

write('P= ',p);

d)

P:=1;

for i:=1 to N do if i mod 2=1 then p:=p*i;

write('P= ',p);

#include <bits/stdc++.h>

using namespace std;

long long m,n,i,t;

int main()

{

cin>>m>>n;

t=0;

for (i=m; i<=n; i++)

if (i%2==1) t=t+i;

cout<<t;

return 0;

}

#include <bits/stdc++.h>

using namespace std;

long long n,i,t;

int main()

{

cin>>n;

t=0;

for (i=1; i<=n; i++)

if (i%2==0) t+=i;

cout<<t;

return 0;

}