CALL BY REFENCE.

swapping the two no.

void main()

{

void myudf(int * , int *); //function declaration ....ansi or modern style.....

int nx , ny ;

int *px , *py ;

px = &nx ;

py = &ny ;

printf("ENTER TWO NO.S ") ;

scanf("%d %d" , px ,py);

myudf(px , py); // funtion calling.....................

printf("BACK TO MAIN: THE FISRT NO IS[%d] AT ADDR [u] SECOND IS :[%d] AT ADDR [%u] " , *px , px , *py , py );

getch();

}

//............END OF MAIN............................

void myudf( int *pnx , int *pny)

{

int z ;

z = *pnx ;

*pnx = *pny ;

*pny = z ;

printf("AT UDF : NOW THE FIRST NO. IS:[%d]AT ADDR [%u] THE SECOND NO.[%d] AT ADDR [%u] " ,*pnx , pnx , *pny , pny );

getch();

}