C++函数模板的重载

#include <iostream>
using namespace std;
template<class T> void Swap(T &a, T &b);  //模板①：交换基本类型的值
template<typename T> void Swap(T a[], T b[], int len);  //模板②：交换两个数组
void printArray(int arr[], int len);  //打印数组元素
int main(){
    //交换基本类型的值
    int m = 10, n = 99;
    Swap(m, n);  //匹配模板①
    cout<<m<<", "<<n<<endl;
    //交换两个数组
    int a[5] = { 1, 2, 3, 4, 5 };
    int b[5] = { 10, 20, 30, 40, 50 };
    int len = sizeof(a) / sizeof(int);  //数组长度
    Swap(a, b, len);  //匹配模板②
    printArray(a, len);
    printArray(b, len);
    return 0;
}
template<class T> void Swap(T &a, T &b){
    T temp = a;
    a = b;
    b = temp;
}
template<typename T> void Swap(T a[], T b[], int len){
    T temp;
    for(int i=0; i<len; i++){
        temp = a[i];
        a[i] = b[i];
        b[i] = temp;
    }
}
void printArray(int arr[], int len){
    for(int i=0; i<len; i++){
        if(i == len-1){
            cout<<arr[i]<<endl;
        }else{
            cout<<arr[i]<<", ";
        }
    }
}

99, 10
10, 20, 30, 40, 50
1, 2, 3, 4, 5