Next permutation

#include
#include
using namespace std;
int main()
{

int t;
cin >> t;

while(t>0)
{
    int n;
	cin >> n;
	int arr[10];
    for (int i = 0; i < n; i++)
    {
        cin >> arr[i];
    }
    
next_permutation(arr, arr + n);
for(int i=0;i<n;i++){
    cout<<arr[i]<<" ";
}
cout<<endl;
t--;
}

return 0;

}

can u plz tell me what is wrong in this?