[백준][Java] 1316번 그룹 단어 체커

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
 
 
public class Main {
        
    private static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    private static BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
    
    public static void main(String[] args) throws IOException{
        // 일단 boolean array로 각 알파벳을 지나쳤는지 check해줌
        int N = Integer.parseInt(br.readLine());
        int result = 0;
        
        
        for(int i=0; i<N; i++) {
            String input = br.readLine();
            if(isGroupWord(input)) result++;
        }
        bw.write(String.valueOf(result));
        bw.flush();
    }
    
    public static boolean isGroupWord(String input) {
        char currentChar = ' ';
        boolean[] isPassed = new boolean[26];
        
        for(int j=0; j<input.length(); j++) {
            if(currentChar!=input.charAt(j)) {
                if(isPassed[input.charAt(j)-'a']) return false;
                isPassed[input.charAt(j)-'a']=true;
                currentChar=input.charAt(j);
            }
        }
        return true;
    }
    
    
}