add kotlin solution for 438 Find-All-Anagrams-In-A-String.kt

MagicienDeCode · MagicienDeCode · commit 086bcf4e8fc1 · 2020-05-17T17:58:15.000+02:00
diff --git a/May-LeetCoding-Challenge/17-Find-All-Anagrams-In-A-String/Find-All-Anagrams-In-A-String.kt b/May-LeetCoding-Challenge/17-Find-All-Anagrams-In-A-String/Find-All-Anagrams-In-A-String.kt
@@ -0,0 +1,72 @@
+class FindAllAnagramsinaStringKotlin438 {
+    fun findAnagrams(s: String, p: String): List<Int> {
+        if (s.isEmpty() || s.length < p.length) {
+            return emptyList()
+        }
+        val result = mutableListOf<Int>()
+        val hashArray = IntArray(26)
+        for (index in p.indices) {
+            ++hashArray[p[index] - 'a']
+        }
+        var left = 0
+        var count = 0
+        /*
+           0 1 2 3 4
+        S: b a b a e ...
+        P: a b b
+        for
+           a  b  e
+        P  1  2  0
+        0  1  1  0  count = 1
+        1  0  1  0  count = 2
+        2  0  0  0  count = 3   left = 0 OK
+        3  0  1  0  count = 2   left = 1 NOT
+        4  1  1  -1  count = 1   left = 2 NOT
+         */
+
+        for (index in s.indices) {
+            if (--hashArray[s[index] - 'a'] >= 0) {
+                ++count
+            }
+            if (index >= p.length) {
+                if (hashArray[s[left++] - 'a']++ >= 0) {
+                    --count
+                }
+            }
+            if (count == p.length) {
+                result.add(left)
+            }
+        }
+        return result
+    }
+    /*
+    fun findAnagrams(s: String, p: String): List<Int> {
+        if (s.isEmpty() || s.length < p.length) {
+            return emptyList()
+        }
+        val result = mutableListOf<Int>()
+        val hashArray = IntArray(26)
+        for (index in p.indices) {
+            ++hashArray[p[index] - 'a']
+            --hashArray[s[index] - 'a']
+        }
+        if (hashArray.count { it == 0 } == 26) {
+            result.add(0)
+        }
+        for (index in 1..s.length - p.length) {
+            ++hashArray[s[index - 1] - 'a']
+            --hashArray[s[index + p.length - 1] - 'a']
+            if (hashArray.count { it == 0 } == 26) {
+                result.add(index)
+            }
+        }
+        return result
+    }
+     */
+}
+
+fun main() {
+    val solution = FindAllAnagramsinaStringKotlin438()
+    println(solution.findAnagrams("cbaebabacd", "abc")) // 0,6
+    println(solution.findAnagrams("abab", "ab")) // 0,1,2
+}
