Add IsPermutationPalindrome

Author: igorwojda

README.md

@@ -58,6 +58,7 @@ your time before you take a look at the presented solution. **Good luck!**
 **Apprentice**
 - [Is palindrome](app/src/test/java/com/igorwojda/string/ispalindrome/basic/IsPalindrome.md)
 - [Is tolerant palindrome](app/src/test/java/com/igorwojda/string/ispalindrome/tolerant/IsTolerantPalindrome.md)
+- [Is permutation palindrome](app/src/test/java/com/igorwojda/string/ispalindrome/permutation/IsPermutationPalindrome.md)
 - [Is anagram](app/src/test/java/com/igorwojda/string/isanagram/IsAnagram.md)
 - [Max occurring char](app/src/test/java/com/igorwojda/string/maxchar/MaxOccurrentChar.md)
 - [String reverse](app/src/test/java/com/igorwojda/string/reverse/Reverse.md)

app/src/test/java/com/igorwojda/string/ispalindrome/permutation/IsPermuntationPalindrome.kt

@@ -0,0 +1,30 @@
+package com.igorwojda.string.ispalindrome.permutation
+
+import org.amshove.kluent.shouldBeEqualTo
+import org.junit.Test
+
+private fun isPermutationPalindrome(str: String): Boolean {
+    TODO("not implemented")
+}
+
+class IsPermutationPalindromeTest {
+    @Test
+    fun `"gikig" is a palindrome`() {
+        isPermutationPalindrome("gikig") shouldBeEqualTo true
+    }
+
+    @Test
+    fun `"ookvk" is a palindrome`() {
+        isPermutationPalindrome("ookvk") shouldBeEqualTo true
+    }
+
+    @Test
+    fun `"sows" is a palindrome`() {
+        isPermutationPalindrome("sows") shouldBeEqualTo false
+    }
+
+    @Test
+    fun `"tami" is a palindrome`() {
+        isPermutationPalindrome("tami") shouldBeEqualTo false
+    }
+}

app/src/test/java/com/igorwojda/string/ispalindrome/permutation/IsPermuntationPalindrome.md

@@ -0,0 +1,25 @@
+# Is permutation palindrome
+
+## Nice to solve before
+
+- [Palindrome](../basic/IsPalindrome.md)
+
+## Instructions
+
+Given a string, return true if the input string is an a permutation of palindrome or false if it is not.
+
+Palindromes are strings that form the same word if it is reversed.
+
+[Puzzle](IsPermutationPalindrome.kt) | [Solution](IsPermutationPalindromeSolution.kt)
+
+## Examples
+
+```
+permutationPalindrome("gikig") == true
+
+permutationPalindrome("ookvk") == true
+
+permutationPalindrome("sows") == false
+
+permutationPalindrome("tami") == false
+```

app/src/test/java/com/igorwojda/string/ispalindrome/permutation/IsPermuntationPalindromeSolution.kt

@@ -0,0 +1,12 @@
+package com.igorwojda.string.ispalindrome.permutation
+
+// frequency map solution
+private object Solution1 {
+    private fun isPermutationPalindrome(str: String, characterRemoved: Boolean = false): Boolean {
+        val charactersFrequencyMap = str.groupingBy { it }.eachCount()
+
+        val filtered = charactersFrequencyMap.filter { it.value % 2 == 1 }
+
+        return filtered.size <= 1
+    }
+}

misc/PuzzleGroups.md

@@ -139,6 +139,7 @@ We use sliding window instead of nested loops which decreases complexity from `O
 - [Is anagram](../app/src/test/java/com/igorwojda/string/isanagram/IsAnagram.md)
 - [Is palindrome](../app/src/test/java/com/igorwojda/string/ispalindrome/basic/IsPalindrome.md)
 - [Is tolerant palindrome](../app/src/test/java/com/igorwojda/string/ispalindrome/tolerant/IsTolerantPalindrome.md)
+- [Is permutation palindrome](app/src/test/java/com/igorwojda/string/ispalindrome/permutation/IsPermutationPalindrome.md)
 - [Is substring](../app/src/test/java/com/igorwojda/string/issubstring/IsSubstring.md)
 - [Longest word](../app/src/test/java/com/igorwojda/string/longestword/LongestWord.md)
 - [Max occurrent char](../app/src/test/java/com/igorwojda/string/maxchar/MaxOccurrentChar.md)

misc/PuzzleOrder.md

@@ -70,4 +70,4 @@ This section contains all puzzles in order in which they where added to reposito
 64. [Doubly linked list](../app/src/test/java/com/igorwojda/linkedlist/doubly/base/DoublyLinkedList.md)
 65. [Binary search tree](../app/src/test/java/com/igorwojda/tree/binarysearchtree/BinarySearchTree.md)
 66. [Max binary heap](../app/src/test/java/com/igorwojda/tree/heap/maxbinaryheap/MaxBinaryHeap.md)
-    
+67. [Is permutation palindrome](app/src/test/java/com/igorwojda/string/ispalindrome/permutation/IsPermutationPalindrome.md)