Question

Nhập n nguyên.

Kiểm tra xem n có phải là số nguyên tố không?

Answer 1

Program nguyento;

Uses Crt;

Var n,d,k:longint;

Begin Clrscr;

write('n=');

Readln(n);

k:=0;

For d:=1 to n do

If n mod d = 0 then

k:=k+1;

If k=2 then

write ('n la so nguyen to');

Readln;

End.

Answer 2

var n:integer;

a,d:word;

begin

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

if n <2 then writeln(n,' khong phai la so nguyen to ')

else begin

d:=0;

for a:=2 to n div 2 do

if (n mod a=0) then d:=d+1;

if d=0 then writeln(n,' la so nguyen to ')

else writeln(n,' khong phai la so nguyen to ');

end;

readln;

end.

Answer 3

program nguyen_to;

uses Crt;

var n,d,k:longint;

begin clrscr;

write('n=');

readln(n);

k:=0;

for d:=1 to n do

if n mod d = 0 then

k:=k+1;

if k=2 then

write ('n la so nguyen to');

readln;

end.