Why quick sort in cpp is not working for :

//i have tried multiple code but i am keeep geeting error
number of 1 can be different but Quick sort is unable to solve it mainly in c++
working fine in python
{2,1,1,1,1,1,1,1,1,1,2}

#include <bits/stdc++.h>
using namespace std;
void swap(vector<int>& v, int x, int y);

void quicksort(vector<int> &vec, int L, int R) {
    int i, j, mid, piv;
    i = L;
    j = R;
    mid = L + (R - L) / 2;
    piv = vec[mid];

    while (i<R || j>L) {
        while (vec[i] < piv)
            i++;
        while (vec[j] > piv)
            j--;

        if (i <= j) {
            swap(vec, i, j); //error=swap function doesnt take 3 arguments
            i++;
            j--;
        }
        else {
            if (i < R)
                quicksort(vec, i, R);
            if (j > L)
                quicksort(vec, L, j);
            return;
        }
    }
}

void swap(vector<int>& v, int x, int y) {
    int temp = v[x];
    v[x] = v[y];
    v[y] = temp;

}

int main() {
    vector<int> vec1 = {2,1,1,1,1,1,1,1,1,1,1,2};
    const int count = 10;

    // for (int i = 0; i < count; i++) {
    //     vec1.push_back(1 + rand() % 100);
    // }
    quicksort(vec1, 0, count - 1);
    for (int i : vec1){
        cout<<i <<"  ";
    }

}

output of the code