函数的值传递和指针传递的区别

#include <iostream>
using namespace std;

//函数的值传递
template<typename T>
void swapValue(T a, T b){
    cout<<"值传递函数开始前a = "<<a<<", "<<"b = "<<b<<endl;
    T temp;
    temp = a;
    a = b;
    b = temp;
    cout << "值传递函数结束在函数内部打印a = "
    <<a<<", "<<"b = "<<b<<endl;
}

//函数的指针传递
template<typename T>
void swapPoint(T *a, T *b){
    cout<<"指针传递函数开始前a的地址为"<<a<<", b的地址为"<<b<<endl;
    cout<<"指针传递函数开始前a的值为"<<*a<<", b的值为"<<*b<<endl;
    T temp = *a;
    *a = *b;
    *b = temp;
    cout<<"指针传递函数开始后函数内打印a的地址为"
    <<a<<", b的地址为"<<b<<endl;
    cout<<"指针传递函数开始后函数内打印a的值为"
    <<*a<<", b的值为"<<*b<<endl;
}

int main() {
    int a = 4;
    int b = 2;
    swapValue<int>(a, b);
    cout << "swapValue函数结束后打印a = "
         <<a<<", "<<"b = "<<b<<endl;
    swapPoint<int>(&a, &b);
    cout<<"swapPoint函数结束后打印a的地址为"
        <<a<<", b的地址为"<<b<<endl;
    cout<<"swapPoint函数开结束后打印a的值为"
        <<&a<<", b的值为"<<&b<<endl;
    return 0;
}

打印输出结果：