[프로그래머스/Java] 가장 가까운 같은 글자

-Code

import java.util.Arrays;
import java.util.Map;
import java.util.HashMap;

class Solution {
    public int[] solution(String s) {
        int[] answer = new int[s.length()];
        Map<Character, Integer> stringMap = new HashMap<>();

        for (int i = 0; i < s.length(); i++) {
            char c = s.charAt(i);
            answer[i] = stringMap.containsKey(c) ? 
                    i - stringMap.get(c) : -1;
            stringMap.put(c, i);
        }
        return answer;
    }
}