var a, b: integer;

Function kt(x: word): boolean;

   Var i: word;

   Begin

       For i:=2 to trunc(sqrt(x)) do

            If x mod i=0 then exit(false);

       Exit(false);

   End;

Begin

   Write('nhap a va b: '); readln(a, b);

   Writeln('tong: ', a+b);

   writeln('tich: ', a*b);

   If kt(a)=true

        then writeln(a, ' la so nguyen to')

   Else writeln(a, ' ko la so nguyen to');

   If kt(b)=true 

        then writeln(b, ' la so nguyen to')

   Else writeln(b, ' ko la so nguyen to');

   Readln

End.

uses crt;
var a,b: integer;

{---Hàm kiểm tra tính nguyên tố---}
    snt:boolean;
function ktnt(c:integer):boolean;
var i:integer;
kt:boolean;
begin
kt:=true;
if c<=1 then kt:=false;
for i:=2 to trunc(sqrt(c)) do
if (c mod i = 0) then kt:=false;
ktnt:=kt;
end;

{----Phần chương trình chính---}
begin
clrscr;
write('Nhap a,b tuong ung: '); readln(a,b);
writeln('Tich a va b : ',a*b);
writeln('Tong a va b: ', a+b);
if ktnt(a) then writeln(a,' la so nguyen to') else writeln(a,' khong la so nguyen to');
 if ktnt(b) then writeln(b,' la so nguyen to') else writeln(b,'khong la so nguyen to');
readln;
end.

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