//只需要把下面代码paste到new project, run, 即看到效果//The goal of this program is to show: // the relationship of Pointer and Address in C languange.
//created by Feb 4th, 2002 //modified by Feb 4th,2004
#include <stdio.h>#include <string.h>#include <stdlib.h>
//if put 3, result=3^3+3=12; //if 4, result=4^4+4=20...double squarePlus(int a,double *b);
int main(void){ double x=3,y=3,result=0; printf("/n 0.....y Address = %p/n",&y); // print y address
//scanf(y); result=squarePlus(3,&y); printf("/n SquarePlus of %f = %2.0f /n",x,result);
return 0;}/*
0.....y Address = 0012FF70 1.....pAddress(b) = 0012FF70 2.....double value(*b) = 3.000000...processing: (*b) *= *b;
SquarePlus of 3.000000 = 12Press any key to continue
*/
//**********************************************************//double squarePlus(int a,double *b){ //Print the address of pointer: printf(" 1.....pAddress(b) = %p /n",b);
//Print the value after calcuation: printf(" 2.....double value(*b) = %f/n",*b);
//Save before you have to change. double k = *b; //b=&k; //[YES] if b= sth's address; // *b= sth's value;
// b is always the Result: *b=a; (*b) *= *b; //multipile itself printf("...processing: (*b) *= *b;/n"); *b=*b+k; //[YES] value itself +1; //b=b+b; //[NO] just make "b" to another address;
return *b; //return (*b)*(*b)+(*b); //[YES] works also //return b; // [NO] cannot convert from 'double *' to 'double'}
//http://www.eurasia.edu/bbs/ti_view.asp?FN_id=15&FC_root_id=115073&FC_id=115073
