C语言函数问题

test1.cpp

/***
 * C语言函数的传值调用与传址调用
 */
# include<stdio.h>
# include<stdlib.h>
# include<conio.h>

int test1(int a,int b);
int test2(int *pa,int *pb);
int test3(int &a,int &b);

int main()
{
  int a = 1;
  int b = 2;
  int *pa = &a;
  int *pb = &b;
  //test1
  printf("a=%d,b=%d\n",test1(a,b));
  //test2
  printf("a=%d,b=%d\n",test2(pa,pb));
  //test3
  printf("a=%d,b=%d\n",test3(&a,&b));
  return 0;
}

int test1(int a,int b)
{
  /*传值调用,仅仅改变了局部变量,全局变量不受影响*/
  int temp;
  temp = a;
  a = b;
  b = temp;
  return a,b;
}

int test2(int *pa,int *pb)
{
  /*传值调用,仅仅改变了局部变量的地址,实参不受影响*/
  int *temp;
  temp = pa;
  pa = pb;
  pb = temp;
  return *pa,*pb;
}

int test3(int &a,int &b)
{
  /*传址调用,直接操纵全局变量的地址*/
  int temp;
  temp = a;
  a = b;
  b = temp;
  return a,b;
}

问题已经解决