백준 6단계 no.10

import java.util.Scanner;

public class Main {
    static boolean checker(String str) {
        char[] strArr = new char[str.length()];
        for (int i = 0; i < strArr.length; i++) {
            strArr[i] = str.charAt(i);
        }
        int[] alphaArr = new int[26];

        alphaArr[strArr[0]-97] += 1;
        for (int j = 1; j < strArr.length; j++) {
            if (strArr[j] != strArr[j-1]) {
                alphaArr[strArr[j]-97] +=1;
            }
        }

        int s = 1;
        for (int i : alphaArr) {
            if (i > 1) {
                s = 0;
                break;
            }
        }

        return s == 1;
    }

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();
        int count = 0;

        for (int i = 0; i < n; i++) {
            String str = sc.next();
            if (checker(str)) {
                count++;
            }
        }

        System.out.println(count);
    }
}