int result(String[] arr) {
    char c1 = 0;
    char c2 = 0;
    for (int i = 0; i < arr.length - 1; i++) {
        c1 = arr[i].charAt(arr[i].length() - 1);
        c2 = arr[i + 1].charAt(0);
        if (c1 != c2) {
            return 0;
        }
    }
    return 1;
}