Unexpected result while passing struct to a function

Unexpected result while passing struct to a function

I want to pass a struct to function something like below (I know i can
pass single member to function like input(int age, string s) but i want to
pass whole struct like input(student s) )
#include <iostream>
using namespace std;
struct student
{
string name;
int age;
};
void input(student s)
{
cout << "Enter Name: ";
cin >> s.name;
cout << "Enter age: ";
cin >> s.age;
}
int main(int argc, char *argv[]) {
struct student s1;
input(s1);
cout << "Name is: " << s1.name << endl;
cout << "Age is: " << s1.age << endl;
}
Above code does not produce correct output, I want to use above code with
pointer so to get expected output.