c++中*和&以及vector两种传参方法

*指针

	int a = 10;
	int *b = &a;

a的值是10，&a是a的存放地址
int *b定义一个指针，这个指针指向地址是a的存放地址，*b = 10,b= &a,b是一个地址

	int &c = a;

这里的int &c 是对a的引用，c++区别c的一点，其中c = a;是个值，&c = &a,是个地址
b,c的改变会导致a的改变

对于vector的传参，知道主函数调用只需要数组名即可
代码及测试结果

#include 
#include 
using namespace std;
void test1(vector<int>test1){
	test1.back() = -1;
	cout << "形式传参函数内数组"<< endl;
	for(int num : test1)cout << num << " ";
	cout << endl;
}
void test2(vector<int>&test1){
	test1.back() = -1;
	cout << "地址传参函数内数组"<< endl;
	for(int num : test1)cout << num << " ";
	cout << endl;
}
int main(){
	int a = 10;
	int *b = &a;
	int &c = a;
	cout << "a  " << a << endl;
	cout << "&a  " << &a << endl;
	cout << "b = &a  " << b << endl;
	cout << "*b = a  " << *b << endl;\
	cout << "c是对a的引用 " << c << endl;
	cout << "&c = a  " << &c  << endl;
	*b = 3;
	cout << "修改*b值a会跟着改变 " << a << endl;
	c = 10;
	cout << "修改c值a也会跟着改变 " << a << endl;
	cout << "数组传参测试" << endl;
	vector<int>test{1,2,3,4,5};
	cout << "初始数组"<<endl;
	for(int num : test)cout << num << " ";
	cout << endl;
	test1(test);
	cout << "形式传参主函数数组"<<endl;
	for(int num : test)cout << num << " ";
	cout << endl;
	test2(test);
	cout << "地址传参后主函数数组"<<endl;
	for(int num : test)cout << num << " ";
	cout << endl;
	return 0;
}