Cho biến i chạy từ 1 đến n. Xét i. Nếu nó là số hoàn chỉnh thì in ra.

Program Tim_uoc_2;

uses crt;

Var S, n, i,j: longint;

Begin

clrscr;

Write('Nhap so n ='); readln(n);

For i:=1 to n do

Begin

S:=0;

For j:=1 to i do if i mod j = 0 then S:=S+j;

if S = 2*i then write(i:6,',');

end;

readln

end.

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 do 

  if i mod j=0 then t:=t+j;

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

end;

readln;

end.

TK

https://www.google.com/url?sa=t&source=web&rct=j&url=https://freetuts.net/thuat-toan-kiem-tra-so-hoan-hao-2919.html&ved=2ahUKEwih6ejz18_0AhVPslYBHVhcBmIQFnoECD8QAQ&usg=AOvVaw0Mb94AOV2KpQWjxBRg9BYD

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 HOC24;

var i,t,k,n: integer;

begin

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

t:=0; k=0;

while k=0 do

begin

n:=n+1;

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

if t=n then

begin

write(n);

k:=k+1

end else t:=0;

end;

readln

end.

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";

}

Program bt_1;

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.