@@ -0,0 +1,473 @@
+import java.util.*;%0A%0Apublic class Problem1_1 %7B%0A  public static void main(String%5B%5D args) %7B%0A    System.out.println(isUniqueChars(%22test%22) + %22 should be false%22);%0A    System.out.println(isUniqueChars(%22tesla%22) + %22 should be true%22);%0A  %7D%0A%0A  public static boolean isUniqueChars(String str) %7B%0A    char%5B%5D chars = str.toCharArray();%0A    Arrays.sort(chars);%0A    for (int i = 0; i %3C chars.length - 1; i++) %7B%0A      if (chars%5Bi%5D == chars%5Bi + 1%5D) return false;%0A    %7D%0A    return true;%0A  %7D%0A%7D%0A

problem 1_1