Program tong;

Uses crt;

Var n , s , k: integer;                            // Khai bao bien su dung

Begin

    Write(‘ Nhap N:’);                           // Thong bao nhap lieu

    Readln(N );                                        // Nhap gtri cho N

    S := 0;

    While ( N <> 0 ) do                      // Lap trong khi N con ≠ 0

    Begin    

            k := N mod 10;                      // Lay chu so hang don vi o cuoi cung

            N :=  N div 10;                      // Cat chu so hang don vi da duoc lay ra

            S := S + k;                              // Tinh tong cong don vao S

    End;

    Writeln( ‘Tong cac chu so cua ’,N,’ la :’, S);   // Xuat ket qua

Readln;

End.