How do I make the function edit a vector created outside the function in C++?

This is my code:

#include <iostream>
#include <vector>
using namespace std;

int BubbleSort(vector<int>, int);

int main(){

    vector<int> lista_y2 {1, 2, 0};
    cout << BubbleSort(lista_y2, lista_y2.size()) << endl;
    cout << lista_y2[0] << lista_y2[1] << lista_y2[2] << endl;
    
    
    return 0;
}


int BubbleSort(vector<int> lista_y2, int m){
    int swaps{0};
    for (int fim {m-1}; fim >= 0; fim--){
        for (int inicio {0}; inicio < fim; inicio++){
            if (lista_y2[inicio] > lista_y2[inicio+1]){
                lista_y2[inicio] = lista_y2[inicio+1] + lista_y2[inicio];
                lista_y2[inicio+1] = lista_y2[inicio] - lista_y2[inicio+1];
                lista_y2[inicio] = lista_y2[inicio] - lista_y2[inicio+1];
                swaps++;
            }
        }
    }
    return swaps;
}

It does return the swaps as it's supose to. But when I try to print the elements from the lista_y2 it has not changed after the BubbleSort. Can someone help me fix it please?

You need to pass the std::vector by reference, or const reference if the function will not modify the parameter. Passing by reference allows your function to modify the parameter.

E.g. : int BubbleSort(vector<int>& lista_y2, int m)

You should pass all large data types by reference so that the compiler doesn't make copies.