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383: Ransom Note

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`@@ -21,6 +21,7 @@ My solutions to LeetCode problems in Kotlin.`
`21`	`21`	`\| [186](https://leetcode.com/problems/reverse-words-in-a-string-ii/) \| [Reverse Words in a String II](src/main/kotlin/com/schmoczer/leetcode/_0186/ReverseWordsInStringInPlace.kt) \| Medium \|`
`22`	`22`	`\| [206](https://leetcode.com/problems/reverse-linked-list/) \| [Reverse Linked List](src/main/kotlin/com/schmoczer/leetcode/_0206/ReverseLinkedList.kt) \| Easy \|`
`23`	`23`	`\| [344](https://leetcode.com/problems/reverse-string/) \| [Reverse String](src/main/kotlin/com/schmoczer/leetcode/_0344/ReverseString.kt) \| Easy \|`
	`24`	`+\| [383](https://leetcode.com/problems/ransom-note/) \| [Ransom Note](src/main/kotlin/com/schmoczer/leetcode/_0383/RansomNote.kt) \| Easy \|`
`24`	`25`	`\| [412](https://leetcode.com/problems/fizz-buzz/) \| [Fizz Buzz](src/main/kotlin/com/schmoczer/leetcode/_0412/FizzBuzz.kt) \| Easy \|`
`25`	`26`	`\| [773](https://leetcode.com/problems/sliding-puzzle/) \| [Sliding Puzzle](src/main/kotlin/com/schmoczer/leetcode/_0773/SlidingPuzzle.kt) \| Hard \|`
`26`	`27`	`\| [796](https://leetcode.com/problems/rotate-string/) \| [Rotate String](src/main/kotlin/com/schmoczer/leetcode/_0796/RotateString.kt) \| Easy \|`

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	`1`	`+# Ransom Note`
	`2`	`+`
	`3`	+Given two strings `ransomNote` and `magazine`, return `true` if `ransomNote` can be constructed by using the letters
	`4`	+from `magazine` and `false` otherwise.
	`5`	`+`
	`6`	+Each letter in `magazine` can only be used once in `ransomNote`.
	`7`	`+`
	`8`	`+Example 1:`
	`9`	`+`
	`10`	`+> Input: ransomNote = "a", magazine = "b"`
	`11`	`+>`
	`12`	`+> Output: false`
	`13`	`+`
	`14`	`+Example 2:`
	`15`	`+`
	`16`	`+> Input: ransomNote = "aa", magazine = "ab"`
	`17`	`+>`
	`18`	`+> Output: false`
	`19`	`+`
	`20`	`+Example 3:`
	`21`	`+`
	`22`	`+> Input: ransomNote = "aa", magazine = "aab"`
	`23`	`+>`
	`24`	`+> Output: true`
	`25`	`+`
	`26`	`+Constraints:`
	`27`	`+`
	`28`	+- `1 <= ransomNote.length, magazine.length <= 10^5`
	`29`	+- `ransomNote` and `magazine` consist of lowercase English letters.

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	`1`	`+package com.schmoczer.leetcode._0383`
	`2`	`+`
	`3`	`+class RansomNote {`
	`4`	`+ // Approach 1: remove letters from magazine, simple & intuitive`
	`5`	`+ fun canConstruct1(ransomNote: String, magazine: String): Boolean {`
	`6`	`+ val magazine = magazine.toMutableList()`
	`7`	`+ for (letter in ransomNote) {`
	`8`	`+ if (!magazine.remove(letter)) {`
	`9`	`+ return false`
	`10`	`+ }`
	`11`	`+ }`
	`12`	`+ return true`
	`13`	`+ }`
	`14`	`+`
	`15`	`+ // Approach 2: map occurrences of a letter into a IntArray`
	`16`	`+ // Runtime 3ms Beats 98.51%`
	`17`	`+ fun canConstruct(ransomNote: String, magazine: String): Boolean {`
	`18`	`+ val alphabet = IntArray(123)`
	`19`	`+ for (letter in magazine) {`
	`20`	`+ alphabet[letter.code]++`
	`21`	`+ }`
	`22`	`+`
	`23`	`+ for (letter in ransomNote) {`
	`24`	`+ if (alphabet[letter.code] == 0) {`
	`25`	`+ return false`
	`26`	`+ }`
	`27`	`+ alphabet[letter.code]--`
	`28`	`+ }`
	`29`	`+`
	`30`	`+ return true`
	`31`	`+ }`
	`32`	`+}`

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	`1`	`+package com.schmoczer.leetcode._0383`
	`2`	`+`
	`3`	`+import org.junit.jupiter.api.Assertions.assertFalse`
	`4`	`+import org.junit.jupiter.api.Assertions.assertTrue`
	`5`	`+import org.junit.jupiter.api.BeforeEach`
	`6`	`+import kotlin.test.Test`
	`7`	`+`
	`8`	`+class RansomNoteTest {`
	`9`	`+ private lateinit var sut: RansomNote`
	`10`	`+`
	`11`	`+ @BeforeEach`
	`12`	`+ fun setUp() {`
	`13`	`+ sut = RansomNote()`
	`14`	`+ }`
	`15`	`+`
	`16`	`+ @Test`
	`17`	+ fun `a can not be constructed from b`() {
	`18`	`+ val note = "a"`
	`19`	`+ val magazine = "b"`
	`20`	`+`
	`21`	`+ assertFalse(sut.canConstruct(note, magazine))`
	`22`	`+ }`
	`23`	`+`
	`24`	`+ @Test`
	`25`	+ fun `aa can not be constructed from ab`() {
	`26`	`+ val note = "aa"`
	`27`	`+ val magazine = "ab"`
	`28`	`+`
	`29`	`+ assertFalse(sut.canConstruct(note, magazine))`
	`30`	`+ }`
	`31`	`+`
	`32`	`+ @Test`
	`33`	+ fun `aa can be constructed from aab`() {
	`34`	`+ val note = "aa"`
	`35`	`+ val magazine = "aab"`
	`36`	`+`
	`37`	`+ assertTrue(sut.canConstruct(note, magazine))`
	`38`	`+ }`
	`39`	`+}`

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