{PROGRAM bai_tap;
USES crt ;
VAR i , n, t:integer;
BEGIN  
  clrscr;
  Write('Nhap n');Readln(n);
  t:=0;
  For i:=1 to n-1 do
  if n mod i=0 then t:=t+i;
  if t=n then write(n,' la so hoan chinh');
  else Writeln(n,' Khong la so hoan chinh');
  Readlnnline Pascal Compiler.
begin    
  End,
Readlnnline
END.

}

#include <bits/stdc++.h>

using namespace std;

long long n,i,t;

int main()

{

cin>>n;

t=0;

for (i=1; i<=n/2; i++) 

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

if (t==n) cout<<"YES";

else cout<<"NO";

return 0;

}

a)

uses crt;

var n,i,t,j:integer;

begin

clrscr;

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

for i:=1 to n do 

  begin

t:=0;

for j:=1 to i-1 do 

 if i mod j=0 then t:=t+j;

if t=i then write(i:4);

end;

readln;

end.

b)

uses crt;

var gt:real;

i,n:integer;

begin

clrscr;

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

gt:=1;

for i:=1 to n do 

 gt:=gt*i;

writeln(gt:0:0);

readln;

end.

program bai_toan;

var

      N, i, sum: integer;

begin

      write('Nhap so N: ');

      readln(N);

      write('Cac uoc cua ', N, ' khong ke ', N, ' la: ');

      for i := 1 to N - 1 do

            if N mod i = 0 then

                  write(i, ' ');

      writeln;

      sum := 0;

      for i := 1 to N - 1 do

      begin

            if N mod i = 0 then sum := sum + i;

      end;

      if sum = N then writeln(N, ' la so hoan hao')

      else writeln(N, ' khong phai la so hoan hao');

      writeln;

      writeln('Tat ca so hoan hao trong pham vi 1 -> ', N, ' la:');

      for i := 1 to N do

      begin

            sum := 0;

            for j := 1 to i - 1 do

            begin

                  if i mod j = 0 then sum := sum + j;

            end;

            if sum = i then writeln(i);

      end;

      readln;

end.

uses crt;

var n,i,t,j:integer;

begin

clrscr;

readln(n);

for i:=1 to n do 

  begin

t:=0;

for j:=1 to i div 2 do 

  if i mod j=0 then t:=t+j;

if t=i then write(i:4);

end;

readln;

end.

program TinhTongVaUoc;

var
  a, b, sum, i: integer;
  uoc: boolean;

begin
  write('Nhap so a: ');
  readln(a);

  write('Nhap so b: ');
  readln(b);

  // Tinh tong a+b
  sum := a + b;
  writeln('Tong cua a va b la: ', sum);

  // In ra cac uoc cua tong
  write('Cac uoc cua tong a+b la: ');
  for i := 1 to sum do
  begin
    if sum mod i = 0 then
      write(i, ' ');
  end;
  writeln;

  // Kiem tra xem tong a+b co phai la so hoan hao hay khong
  uoc := false;
  for i := 1 to sum - 1 do
  begin
    if sum mod i = 0 then
      uoc := true;
  end;
  if uoc and (sum = 2 * sum div 2) then
    writeln('Tong a+b la so hoan hao')
  else
    writeln('Tong a+b khong phai la so hoan hao');
end.

Dùng app đúng không ạ.

2:

#include <bits/stdc++.h>

using namespace std;

int main()

{

int n,i,kt=0;

cin>>n;

for (int i=2; i*i<=n; i++)

if (n%i==0) kt=1;

if (kt==0) cout<<"YES";

else cout<<"NO";

}

uses crt;

var n,i,t:integer;

begin

clrscr;

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

t:=0;

for i:=1 to n-1 do 

  if n mod i=0 then t:=t+i;

if t=n then writeln(n,' la so hoan chinh')

else writeln(n,' khong la so hoan chinh');

readln;

end.

program hoan_chinh;

uses crt;

var n,i,s:integer;

begin

clrscr;

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

for i:=1 to n-1 do

 begin

 if n mod i = 0 then s:=s+i;

 end;

if s=n then writeln('1') {n là số chính phương thì viết 1}

else writeln('0');{n không là số chính phương thì viết 0}

end.