Passing array lengths through templates to functions in C + +

We know that in C + +, when an array is passed to a function, it actually transmits the first address of the array, which is a pointer type. So, in a function, we have no way of knowing how long the length of the array is passing in, and a common way is to add another parameter to record the length of the array passed in.

In C + +, however, using the template mechanism is a good way to solve this problem, as shown in the following code:

#include <iostream>
using namespace std;
template<class T, int N>
void array(T (&param)[N])
{
　　cout << "N= " << N << endl;
}
int main()
{
　　int i[100];
　　double d[20];
　　char c[6];
　　array(i);
　　array(d);
　　array(c);
　　return 0;
}