Write a function to count number of Palindrome substrings in given string?

Question

Given a string aaaabaabaaaa(s to be generic), how many possible palindrome of size > 2 (n to be generic) can be generated from this string?

I need to know how to count number of palindromes and to print those.

Eg. for above string aaa, aaaa, aba, aba, aaa, aaaa, abaaba, aaaabaabaaaa.

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I'll give you the answer, you can do it in O(n), the hard part is figuring out the algorithm. Good luck! — OmnipotentEntity, Dec 26 '13 at 06:48
in the examples mentioned only `aabbccbbaa` is palindrome, isn't it? — Amir Pashazadeh, Dec 26 '13 at 06:48
possible duplicate: http://stackoverflow.com/questions/13977129/how-to-count-the-number-of-words-of-the-samepalindrome-in-java — Kamlesh Arya, Dec 26 '13 at 06:48
@Kamlesh This is not duplicate, that is to find from sentence to word, but its a substring palindrome. — TestUser, Dec 26 '13 at 07:00

score 0 · Accepted Answer · answered Dec 26 '13 at 07:18

 public void palindrome(String string)
 {
    char[] charArray = string.toCharArray();

    count = 0;
    i = 0;
    while(i < charArray.lenght)
    {
       if(charArray[i] == charArray[charArray.lenght - i - 1])
       {
       }
       else
       {
           System.out.println("not a palindrome");
           break;
       }
    }
}

this is the basic logic to test if it is a palindrome.

if the length of the string is even then "" is a palindrome as well or if it is odd the middle char is also a palindrome. So if((string.length()%2) == 0) then it is even or else it is an odd.

I will let you figure the rest out.

hit you might want to take the original sting and make a charArray then rebuild the string one char at a time. You could call the method up above with each iteration of the loop and you will need to add a return statement to the method above. — drhunn, Dec 26 '13 at 07:21

Write a function to count number of Palindrome substrings in given string?

1 Answers1