浅析c/c++中函数的参数传递

#include <cstdlib>
#include <iostream>
using namespace std;
void change1(int n)
{
     cout << "值传递--函数操作地址" << &n << endl;
     n ++;
}
void change2(int &n)
{
     cout << "引用传递--函数操作地址:" << &n << endl;
     n ++;
}
void change3(int *n)
{
     cout << "指针传递--函数操作地址" << n << endl;
     *n = *n + 1;
}
int main(int argc)
{
    int n = 10;
    cout << "实参地址:" << &n << endl;
    cout << "原值 n =" << n << endl;
    change1(n);
    cout << "afterchange1 n =" << n << endl;
    change2(n);
    cout << "afterchange2 n =" << n << endl;
    change3(&n);
    cout << "afterchange3 n =" << n << endl;

    system("PAUSE");
    return EXIT_SUCCESS;
}

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <iostream>
using namespace std;
void init(char *p)
{
    p = (char *)malloc(100);
    cout << "指针传递--函数操作地址" << p << endl;
}

int main()
{
    char *p = NULL;
    cout << "实参原地址" << p  << endl;
    init(p);   

    if(p)
    {
        strcpy(p, "hello");
        printf("%s \n", p);
    }
    else
    {
        printf("%s", "p not init \n");
    }
    free(p);
    system("PAUSE");
    return EXIT_SUCCESS;
}