Connection Status:
Competition Arena > PalindromesCount
Member Single Round Match 474 · 2009-12-03 · by maksay · Brute Force, Simple Search, Iteration
Class Name: PalindromesCount
Return Type: int
Method Name: count
Arg Types: (string, string)
Problem Statement

Problem Statement

A palindrome is a string that is the same whether it is read from left to right or from right to left. Little Dazdraperma likes palindromes a lot. As a birthday gift she received two strings A and B. Now she is curious if there is a way to insert string B into string A so that the resulting string is a palindrome. You agreed to help her and even tell how many different variants of such insertions exist. Two variants are considered different if string B is inserted in different places. Return the number of possible insertion variants.

For example, let A="aba" and B="b". You can insert B in 4 different places:
  • Before the first letter of A. The result is "baba" and it is not a palindrome.
  • After the first letter 'a'. The result is "abba" and it is a palindrome.
  • After the letter 'b'. The result is "abba" and it is also a palindrome.
  • After the second letter 'a'. The result is "abab" and it is not a palindrome.
So, the answer for this example is 2.

Constraints

  • A and B will each contain between 1 and 50 characters, inclusive.
  • Each character of A and B will be a lowercase letter ('a'-'z').
Examples
0)
"aba"
"b"
Returns: 2

The example from the problem statement.

1)
"aa"
"a"
Returns: 3

Here every possible insertion point gives you a palindrome.

2)
"aca"
"bb"
Returns: 0

No possible solutions.

3)
"abba"
"abba"
Returns: 3
4)
"topcoder"
"coder"
Returns: 0

Submissions are judged against all 119 archived test cases, of which 5 are shown here. Case numbers match the judge’s.

Coding Area

Language: C++17 · define a public class PalindromesCount with a public method int count(string A, string B) · 119 test cases · 2 s / 256 MB per case

Submitting as anonymous