#include <bits/stdc++.h>

using namespace std;

long long m,n;

//chuongtrinhcon

long long ucln(long long m,long long n)

{

if (n==0) return(m);

else return(ucln(n,m%n));

}

//chuongtrinhchinh

int main()

{

cin>>n>>m;

cout<<ucln(n,m);

return 0;

}

Pascal bạn ơi

Câu 1: 

uses crt;

var m,n,ucln,i:integer;

begin

clrscr;

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

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

ucln:=1;

if m<n then 

begin

for i:=1 to m do 

if (m mod i=0) and (n mod i=0) then 

  begin

if ucln<i then ucln:=i;

end;

end

else begin

for i:=1 to n do 

  if (m mod i=0) and (n mod i=0) then 

begin

if ucln<i then ucln:=i;

end;

end;

writeln(ucln);

readln;

end.

Câu 2: 

uses crt;

var m,n,bcnn,i:integer;

begin

clrscr;

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

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

bcnn:=m*n;

for i:=m*n-1 downto 1 do 

  if (i mod m=0) and (i mod n=0) then

begin

if bcnn>i then bcnn:=i;

end;

writeln(bcnn);

readln;

end.

BCNN:

program boichung;
var m,n: word;

procedure Input;
        begin
            readln(m,n);
        end;

function BC(m,n: word): word;
var i: word;
       begin
           for i := 1 to n * m do
               if (i mod n = 0) and (i mod m = 0) then
                   write(i,' ');
       end;

begin
    Input;
    BC(m,n);
end.

UCLN:

program UCLN;
var m,n,r,i: longint;
begin
readln(n,m);

n := abs(n);
m := abs(m);

if (n = 0) then
    begin
        i := 1;
        write(m);
    end
else
    if (m = 0) then
        begin
            i := 1;
            write(n);
        end;

r := n mod m;
while r <> 0 do
      begin
        r := n mod m;
        n:= m;
        m:= r;
      end;
if (i = 0) then
    write(n);

readln    
end.

Cái này đâu phải lớp 10, cũng đâu phải môn tin?😮

#include <bits/stdc++.h>

using namespace std;

long long m,n;

//chuongtrinhcon

long long ucln(long long a,long long b)

{

if (b==0) return(a);

else return(ucln(b,a%b));

}

//chuongtrinhchinh

int main()

{

cin>>a>>b;

cout<<ucln(a,b);

return 0;

}

1) var a,b,c,d,h,g:integer;

begin

write('a=');readln(a);

write('b=');readln(b);

write('c=');readln(c);

write('d=');readln(d);

h:=a;

if b>h then h:=b;

if c>h then h:=c;

if d>h then h:=d;

g:=a;

if b<g then g:=b;

if c<g then g:=c;

if d<g then g:=d;

writeln(' So lon nhat trong 4 so la: ',h);

writeln(' So be nhat trong 4 so la: ',g);

readln;

end.

2) var a:integer;

begin

write('a=');readln(a);

if a mod 2=0 then writeln(a,' la so chan ')

else writeln(a,' la so le ');

readln;

end.

5) var a,b,m,n:integer;

begin

write('a=');readln(a);

write('b=');readln(b);

m:=a;

n:=b;

while m<>n do

begin

if m>n then m:=m-n

else n:=n-m;

end;

writeln(' Uoc chung lon nhat cua 2 so la: ',m);

writeln(' Boi chung nho nhat cua 2 so la: ',a*b div n);

readln;

end.

Bài 1:

uses crt;

var n,i,s:integer;

begin

clrscr;

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

s:=0;

for i:=1 to n do 

 if i mod 6=0 then s:=s+i;

writeln(s);

readln;

end.

Bài 2: 

uses crt;

var a,b,c,ucln,i:integer;

begin

clrscr;

write('a='); readln(a);

write('b='); readln(b);

write('c='); readln(c);

while a<>b do 

  begin

if a>b then a:=a-b

else b:=b-a;

end;

ucln:=a;

while ucln<>c do 

 begin

if ucln>c then ucln:=ucln-c

else c:=c-ucln;

end;

writeln(ucln);

readln;

end.

Scratch hay java

2.2.3=12.USCLN (12) :2;3;4;6;12;1

BSCLN:(1;2;3...............)

Chúc bạn học tốt nha

TL:

2.2.3=12.USCLN (12) :2;3;4;6;12;1

BSCLN:(1;2;3...............)

^H T^

làm c++