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Array of strings contains only anagrams?

I was given anagram exercise, and it looked so simple that I doubt that I have something missing. The solution that I implemented is the one that I will bring shortly, and I wanted to ask you if you could think of any optimization, a change in approach, or a problem with my solution. I implemented the algorithm in Java.

Now exercise. As input, I have text, and as a result, I must return whether each line of this text is an anagram of every other line. That is, for input:

Cabin crew Huffiest Minnows Loll Cabin
house Huffy Minnov Lolls
Cabin crew shuffle a million US dollars Cabin crew shuffle a millionth city

The program should return True. To enter:

Cabin crew Huffiest Minnows Loll Cabin crew Huffiest
Minnow Lolls hi
Cabin crew shuffles a million US dollars Cabin crew shuffles a millionth city

the output should be False (due to the second line, of course).

Now, I thought, quite simply:

  • I create 2 HashMap: ref and cur.
  • I am parsing the first line of text by filling out the link. I will only count letters in alphabetical order.
  • for every other line, I parse the line in cur and check if cur.equals (ref): if so return false
  • If I get to the end of the text, this means that each line is an anagram of every other line, so I return true.

And ... that would be so. I tried it with 88,000 line input and it works pretty fast.

Any comments? Suggestions? Optimization?

Thank you very much for your help.

+5
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public static void time(String name, int repetitions, Function function,
        int expectedResult) throws Exception {
    long total = 0;
    for (int i = 0; i < repetitions; i++) {
        System.gc();
        long start = System.currentTimeMillis();
        int result = function.call();
        long end = System.currentTimeMillis();
        if (result != expectedResult) {
            System.out.println("Oops, " + name + " is broken");
            return;
        }
        total += end - start;
    }
    System.out.println("Executution of " + name + " took "
            + (total / repetitions) + " ms on average");
}

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Execution of testWithHashMap took 158 ms on average
Execution of testWithSorting took 76 ms on average
Execution of testWithArray took 56 ms on average

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  • If you set limits on the length of anagrams, you can save more space by using short[]or even byte[]for the number of characters.

+2
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