#include <iostream>

using namespace std;

int trytochange(int);

int trytochange(int i) {
    cout << "i at begining " << i << endl;

    i=100;

    cout << "i at end " << i << endl;

    return i;
}

int main() {
    int x=1;

    cout << "x at start: " << x << endl;
    x=trytochange(x);
    cout << "x at end " << x << endl;

    return 0;
}