같은 숫자는 싫어

#include <iostream>
#include <vector>

using namespace std;

vector<int> solution(vector<int> arr) 
{
    int n=arr.size();
    vector<int> answer;
    answer.push_back(arr[0]);
    for(int i=1;i<n;i++){
        if(arr[i]!=arr[i-1])
            answer.push_back(arr[i]);
    }
    
    cout << "Hello Cpp" << endl;

    return answer;
}

int main()
{
    cout << "Hello world!" << endl;
    return 0;
}