Function ngto(a:longint):boolean; Var i: longint; Begin If i<2 then exit(false); For i:=2 to n div 2 do If n mod i = 0 then exit(false); exit(true); End;
Begin Clrscr; Write('Nhap n: '); Readln(n); If ngto(n) then Write(n,' la so nguyen to') Else Write(n,' khong phai la so nguyen to'); Readln End.
