uses crt;

Var

    x,y,chon: integer;

Begin

    clrscr;

    writeln('Hay lua chon phep tinh: ');

    writeln('1. Phep cong');

    writeln('2. Phep tru');

    writeln('3. Phep nhan');

    writeln('4. Phep chia');

    write('Nhap x: '); readln(x);

    write('Nhap y: '); readln(y);

    write('Nhap phep toan muon thuc hien: '); readln(chon);

    if chon=1 then writeln(x,' cong ',y,' bang ',x+y);

    if chon=2 then writeln(x,' tru ',y,' bang ',x-y);

    if chon=3 then writeln(x,' nhan ',y,' bang ',x*y);

    if chon=4 then writeln(x,' chia ',y,' bang ',x/y);

    readln;

End.

uses crt;

var a,x,y,S:integer;

begin

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

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

writeln(' Chon phep tinh: 1=+,2=-,3=*,4=/');

write('Bn chon phep tinh nao (nhap 1,2,3,4):');readln(a);

if a=1 then S:=x+y;

if a=2 then S:=x-y;

if a=3 then S:=x*y;

if a=4 then S:=x/y;

writeln('S=',S);

readln;

end.