https://school.programmers.co.kr/learn/courses/30/lessons/12906
#include <vector>
#include <iostream>
using namespace std;
vector<int> solution(vector<int> arr)
{
vector<int> answer;
answer.push_back(arr[0]);
for(int i = 1 ; i < arr.size(); i++)
{
if(arr[i] != arr[i - 1]) answer.push_back(arr[i]);
}
return answer;
}
1트 성공!!