[Swift]LeetCode748. 最短完整词 | Shortest Completing Word
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Find the minimum length word from a given dictionary words
, which has all the letters from the string licensePlate
. Such a word is said to complete the given string licensePlate
Here, for letters we ignore case. For example, "P"
on the licensePlate
still matches "p"
on the word.
It is guaranteed an answer exists. If there are multiple answers, return the one that occurs first in the array.
The license plate might have the same letter occurring multiple times. For example, given a licensePlate
of "PP"
, the word "pair"
does not complete the licensePlate
, but the word "supper"
does.
Example 1:
Input: licensePlate = "1s3 PSt", words = ["step", "steps", "stripe", "stepple"] Output: "steps" Explanation: The smallest length word that contains the letters "S", "P", "S", and "T". Note that the answer is not "step", because the letter "s" must occur in the word twice. Also note that we ignored case for the purposes of comparing whether a letter exists in the word.
Example 2:
Input: licensePlate = "1s3 456", words = ["looks", "pest", "stew", "show"] Output: "pest" Explanation: There are 3 smallest length words that contains the letters "s". We return the one that occurred first.
Note:
licensePlate
will be a string with length in range[1, 7]
.licensePlate
will contain digits, spaces, or letters (uppercase or lowercase).words
will have a length in the range[10, 1000]
.- Every
words[i]
will consist of lowercase letters, and have length in range[1, 15]
.
如果单词列表(words
)中的一个单词包含牌照(licensePlate
)中所有的字母,那么我们称之为完整词。在所有完整词中,最短的单词我们称之为最短完整词。
单词在匹配牌照中的字母时不区分大小写,比如牌照中的 "P"
依然可以匹配单词中的 "p"
字母。
我们保证一定存在一个最短完整词。当有多个单词都符合最短完整词的匹配条件时取单词列表中最靠前的一个。
牌照中可能包含多个相同的字符,比如说:对于牌照 "PP"
,单词 "pair"
无法匹配,但是 "supper"
可以匹配。
示例 1:
输入:licensePlate = "1s3 PSt", words = ["step", "steps", "stripe", "stepple"] 输出:"steps" 说明:最短完整词应该包括 "s"、"p"、"s" 以及 "t"。对于 "step" 它只包含一个 "s" 所以它不符合条件。同时在匹配过程中我们忽略牌照中的大小写。
示例 2:
输入:licensePlate = "1s3 456", words = ["looks", "pest", "stew", "show"] 输出:"pest" 说明:存在 3 个包含字母 "s" 且有着最短长度的完整词,但我们返回最先出现的完整词。
注意:
- 牌照
(licensePlate)
的长度在区域[1, 7]
中。 - 牌照
(licensePlate)
将会包含数字、空格、或者字母(大写和小写)。 - 单词列表
(words)
长度在区间[10, 1000]
中。 - 每一个单词
words[i]
都是小写,并且长度在区间[1, 15]
中。
104ms
1 class Solution { 2 func shortestCompletingWord(_ licensePlate: String, _ words: [String]) -> String { 3 var dict = [Character: Int]() 4 for char in licensePlate { 5 if (char >= "a" && char <= "z") || (char >= "A" && char <= "Z") { 6 let lowerCaseChar = char.toLowerCase() 7 if let value = dict[lowerCaseChar] { 8 dict[lowerCaseChar] = value + 1 9 } else { 10 dict[lowerCaseChar] = 1 11 } 12 } 13 } 14 var answer = "" 15 var count = 1001 16 17 for word in words { 18 let wordCount = word.count 19 if wordCount >= count { 20 continue 21 } 22 var wordDict = [Character: Int]() 23 for char in word { 24 if let value = wordDict[char] { 25 wordDict[char] = value + 1 26 } else { 27 wordDict[char] = 1 28 } 29 } 30 31 var completed = true 32 for key in dict.keys { 33 if let value = wordDict[key] { 34 if value < (dict[key]!) { 35 completed = false 36 } 37 } else { 38 completed = false 39 break 40 } 41 } 42 if completed, wordCount < count { 43 answer = word 44 count = answer.count 45 } 46 } 47 return answer 48 } 49 } 50 51 extension Character { 52 static let upperToLowerDict: [Character: Character] = ["A": "a", "B": "b", "C": "c", "D": "d", "E": "e", "F": "f", "G": "g", 53 "H": "h", "I": "i", "J": "j", "K": "k", "L": "l", "M": "m", "N": "n", 54 "O": "o", "P": "p", "Q": "q", "R": "r", "S": "s", "T": "t", "U": "u", 55 "V": "v", "W": "w", "X": "x", "Y": "y", "Z": "z"] 56 func toLowerCase() -> Character { 57 if self >= "a" && self <= "z" { 58 return self 59 } else { 60 return Character.upperToLowerDict[self]! 61 } 62 } 63 }
1 class Solution { 2 func shortestCompletingWord(_ licensePlate: String, _ words: [String]) -> String { 3 var counter:[Int] = [Int](repeating:0,count:26) 4 for c in licensePlate 5 { 6 if (c <= "z") && (c >= "a") {counter[c.ascii - 97] += 1} 7 if (c <= "Z") && (c >= "A") {counter[c.ascii - 65] += 1} 8 } 9 var foundAns:Bool = false 10 var ans:String = String() 11 for s in words 12 { 13 var count:[Int] = [Int](repeating:0,count:26) 14 for c in s 15 { 16 if (c <= "z") && (c >= "a") {count[c.ascii - 97] += 1} 17 if (c <= "Z") && (c >= "A") {count[c.ascii - 65] += 1} 18 } 19 var found:Bool = true 20 for i in 0..<26 21 { 22 if counter[i] > count[i] 23 { 24 found = false 25 break 26 } 27 } 28 if found 29 { 30 if (!foundAns) || (ans.count > s.count) 31 { 32 ans = s 33 } 34 foundAns = true; 35 } 36 } 37 return ans 38 } 39 } 40 41 //Character扩展 42 extension Character 43 { 44 //Character转ASCII整数值(定义小写为整数值) 45 var ascii: Int { 46 get { 47 return Int(self.unicodeScalars.first?.value ?? 0) 48 } 49 } 50 }
120ms
1 class Solution { 2 private let set: Set<Character> = Set(Array("abcdefghijklmnopqrstuvwxyz")) 3 4 func shortestCompletingWord(_ licensePlate: String, _ words: [String]) -> String { 5 let license = freq(licensePlate) 6 var result: String? = nil 7 8 for word in words { 9 if let r = result, word.count >= r.count { 10 continue 11 } 12 13 let f = freq(word) 14 var valid = true 15 for (key, value) in license { 16 let fv = f[key, default: 0] 17 if fv < value { 18 valid = false 19 break 20 } 21 } 22 23 if valid { 24 result = word 25 } 26 } 27 28 return result ?? "" 29 } 30 31 private func freq(_ str: String) -> [Character: Int] { 32 var dict = [Character: Int]() 33 34 for char in Array(str.lowercased()) { 35 guard set.contains(char) else { continue } 36 dict[char] = dict[char, default: 0] + 1 37 } 38 39 return dict 40 } 41 }
124ms
1 class Solution { 2 func shortestCompletingWord(_ licensePlate: String, _ words: [String]) -> String { 3 // let letters = String(licensePlate.unicodeScalars.filter ({ CharacterSet.letters.contains($0) })).lowercased() 4 let letters = licensePlate.components(separatedBy: CharacterSet.letters.inverted).joined(separator: "").lowercased() 5 // print(letters) 6 7 8 var shortestAnswer = "" 9 10 let lowers = words.map({ $0.lowercased() }) 11 12 for word in lowers { 13 var test = letters 14 15 for c in word { 16 if let idx = test.index(of: c) { 17 test.remove(at: idx) 18 19 if test.count == 0 { 20 break 21 } 22 } else { 23 continue 24 } 25 } 26 27 if test.count == 0 { 28 if word.count < shortestAnswer.count { 29 shortestAnswer = word 30 } 31 if shortestAnswer.count == 0 { 32 shortestAnswer = word 33 } 34 } 35 36 } 37 38 return shortestAnswer 39 } 40 }
136ms
1 class Solution { 2 func shortestCompletingWord(_ licensePlate: String, _ words: [String]) -> String { 3 // var words = words.sorted{ $0.count < $1.count } 4 var licensePlate = licensePlate.lowercased() 5 var total = 0 6 var freq = [Character: Int]() 7 for c in licensePlate { 8 guard c >= "a", c <= "z" else { continue } 9 freq[c, default: 0 ] += 1 10 total += 1 11 } 12 var res = "" 13 for s in words { 14 var cnt = total 15 var t = freq 16 for c in s { 17 t[c, default: 0] -= 1 18 if t[c]! >= 0 { cnt -= 1 } 19 } 20 if cnt == 0 && (res.isEmpty || res.count > s.count) { 21 res = s 22 } 23 } 24 return res 25 } 26 }
144ms
1 class Solution { 2 func shortestCompletingWord(_ licensePlate: String, _ words: [String]) -> String { 3 var licensePlateCounts = [Character: Int]() 4 5 for char in licensePlate.lowercased() { 6 if ("a"..."z").contains(char) { 7 licensePlateCounts[char, default: 0] += 1 8 } 9 } 10 11 let sortedWords = words.enumerated().sorted { 12 if $0.element.count == $1.element.count { 13 return $0.offset < $1.offset 14 } else { 15 return $0.element.count < $1.element.count 16 } 17 }.map { $0.element } 18 19 for word in sortedWords { 20 var countsDict = licensePlateCounts 21 for char in word { 22 if let count = countsDict[char] { 23 if count > 1 { 24 countsDict[char] = count - 1 25 } else { 26 countsDict[char] = nil 27 } 28 } 29 30 if countsDict.isEmpty { 31 return word 32 } 33 } 34 } 35 return "impossible" 36 } 37 }
152ms
1 class Solution { 2 func shortestCompletingWord(_ licensePlate: String, _ words: [String]) -> String { 3 var dp = [Character:Int]() 4 for item in licensePlate.lowercased(){ 5 if item >= Character("a") && item <= Character("z"){ 6 dp[item, default:0] += 1 7 } 8 } 9 var result = "1" 10 for item in words { 11 var temp = [Character:Int]() 12 for subitem in item.lowercased(){ 13 if subitem >= Character("a") && subitem <= Character("z"){ 14 temp[subitem, default:0] += 1 15 } 16 } 17 var flag = true 18 for (key,value) in dp{ 19 if value > temp[key, default:0]{ 20 flag = false 21 break 22 } 23 } 24 if flag { 25 if result == "1"{ 26 result = item 27 }else{ 28 result = item.count >= result.count ? result : item 29 } 30 } 31 } 32 33 return result 34 } 35 }
156ms
1 class Solution { 2 func shortestCompletingWord(_ licensePlate: String, _ words: [String]) -> String { 3 4 var plateDict = Dictionary(Array(licensePlate).filter{ ("a"..."z").contains(String($0).lowercased()) }.map { (String($0).lowercased(), 1) }, uniquingKeysWith: +) 5 var length = Int.max 6 var result = "" 7 print(plateDict) 8 for word in words { 9 let wordDict = Dictionary( word.map{ (String($0).lowercased(), 1) }, uniquingKeysWith: +) 10 if isMatch(plateDict, wordDict) { 11 if word.count < length { 12 length = word.count 13 result = word 14 } 15 } 16 } 17 return result 18 } 19 20 fileprivate func isMatch(_ dictA: [String: Int], _ dictB:[String: Int]) -> Bool { 21 for (key, value) in dictA { 22 guard let count = dictB[key] else { 23 return false 24 } 25 if value > count { 26 return false 27 } 28 } 29 return true 30 } 31 }
164ms
1 class Solution { 2 func shortestCompletingWord(_ licensePlate: String, _ words: [String]) -> String { 3 4 var dictLicense: [Character: Int] = [:] 5 var arrayOfChars = Array(licensePlate).map { Character(String($0).lowercased()) } 6 7 for character in arrayOfChars { 8 if(character >= "a" && character <= "z") { 9 if dictLicense[character] == nil { 10 dictLicense[character] = 1 11 } else { 12 dictLicense[character] = dictLicense[character]! + 1 13 } 14 } 15 16 } 17 18 //print(dictLicense) 19 20 let covertedArrayToDicts = words.map { convertkWord($0) } 21 22 let letIsValidArray = covertedArrayToDicts.map { compare(wordDict: $0, licensePlateDict: dictLicense) } 23 24 print(letIsValidArray) 25 26 27 var maxLength = 20 28 var maxIndex = 0 29 30 for (index,isValid) in letIsValidArray.enumerated() { 31 32 if isValid == true { 33 let word = words[index] 34 let length = Array(word).count 35 if length < maxLength { 36 maxLength = length 37 maxIndex = index 38 } 39 } 40 41 } 42 43 return words[maxIndex] 44 } 45 46 func compare(wordDict: [Character: Int], licensePlateDict: [Character: Int]) -> Bool { 47 var copy = wordDict 48 49 50 for key in licensePlateDict.keys { 51 52 if copy[key] != nil { 53 54 copy[key] = copy[key]! - licensePlateDict[key]! 55 56 if copy[key] == 0 { 57 copy[key] = nil 58 } else if copy[key]! < 0 { 59 return false 60 } else { 61 62 } 63 } else { 64 return false 65 } 66 } 67 return true 68 69 } 70 71 func convertkWord(_ string: String) -> [Character: Int] { 72 73 let chars = Array(string) 74 var dict: [Character: Int] = [:] 75 76 for character in chars { 77 if dict[character] == nil { 78 dict[character] = 1 79 } else { 80 dict[character] = dict[character]! + 1 81 } 82 83 } 84 return dict 85 } 86 87 }
168ms
1 class Solution { 2 func shortestCompletingWord(_ licensePlate: String, _ words: [String]) -> String { 3 var licensePlate = licensePlate 4 licensePlate = licensePlate.lowercased() 5 var pattern = [String:Int]() 6 for char in licensePlate.unicodeScalars { 7 if char.value >= 97 && char.value <= 122 { 8 pattern["\(char)",default:0] += 1 9 } 10 } 11 var counts = [String:Int]() 12 var result = "" 13 for word in words { 14 if word.count >= pattern.count { 15 counts = [String:Int]() 16 for char in word { 17 counts["\(char)",default:0] += 1 18 } 19 var flag = true 20 for (k,v) in pattern { 21 guard let value = counts[k], value >= v else { 22 flag = false 23 break 24 } 25 } 26 if flag { 27 if result == "" { 28 result = word 29 }else { 30 result = word.count < result.count ? word : result 31 } 32 } 33 } 34 } 35 return result 36 } 37 }