[Level 2] 영어 끝말잇기

import java.util.*;

class Solution {
    public int[] solution(int n, String[] words) {
        int[] answer = new int[2];
        List<String> list = new ArrayList<>();
        list.add(words[0]);
        
        for(int i=1; i<words.length; i++) {
            String w1 = words[i-1];
            String w2 = words[i];
            
            if(w1.charAt(w1.length()-1)!=w2.charAt(0) || list.contains(w2)) {
                answer[0] = i%n+1;
                answer[1] = i/n+1;
                break;
            }
            
            list.add(w2);
        }
        
        return answer;
    }
}