완주하지 못한 선수

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

string solution(vector<string> participant, vector<string> completion) {
   
    sort(participant.begin(), participant.end());
	sort(completion.begin(), completion.end());

	for (int i = 0; i < participant.size(); i++)
	{
		if (participant[i] != completion[i])
		{
			return participant[i];
		}
	}
    
}