[Swift]LeetCode1122. 数组的相对排序 | Relative Sort Array

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Given two arrays arr1 and arr2, the elements of arr2 are distinct, and all elements in arr2 are also in arr1.

Sort the elements of arr1 such that the relative ordering of items in arr1 are the same as in arr2.  Elements that don't appear in arr2 should be placed at the end of arr1 in ascending order. 

Example 1:

Input: arr1 = [2,3,1,3,2,4,6,7,9,2,19], arr2 = [2,1,4,3,9,6]
Output: [2,2,2,1,4,3,3,9,6,7,19] 

Constraints:

• arr1.length, arr2.length <= 1000
• 0 <= arr1[i], arr2[i] <= 1000
• Each arr2[i] is distinct.
• Each arr2[i] is in arr1.

---

给你两个数组，arr1 和 arr2，

• arr2 中的元素各不相同
• arr2 中的每个元素都出现在 arr1 中

对 arr1 中的元素进行排序，使 arr1 中项的相对顺序和 arr2 中的相对顺序相同。未在 arr2 中出现过的元素需要按照升序放在 arr1 的末尾。 

示例：

输入：arr1 = [2,3,1,3,2,4,6,7,9,2,19], arr2 = [2,1,4,3,9,6]
输出：[2,2,2,1,4,3,3,9,6,7,19] 

提示：

• arr1.length, arr2.length <= 1000
• 0 <= arr1[i], arr2[i] <= 1000
• arr2 中的元素 arr2[i] 各不相同
• arr2 中的每个元素 arr2[i] 都出现在 arr1 中

---

8ms

class Solution {
    func relativeSortArray(_ arr1: [Int], _ arr2: [Int]) -> [Int] {
      var dict = [Int: Int]()
      var result = [Int]()
      for a in arr1 {
        dict[a] = (dict[a] ?? 0)+1
      }

      for a in arr2 {
        if let val = dict[a] {
          for i in 0..<val {
            result.append(a)
          }
          dict.removeValue(forKey: a)
        }
      }
      var simpleArray = [Int]()
      if !dict.isEmpty {
        for (key,val) in dict {
          for i in 0..<val {
            simpleArray.append(key)
          }
          dict.removeValue(forKey: key)
        }
      }
      result.append(contentsOf: simpleArray.sorted())
      return result
    }
}

---

12ms

class Solution {
    func relativeSortArray(_ arr1: [Int], _ arr2: [Int]) -> [Int] {
         var dict = Dictionary<Int,Int>()
        
        for value in arr1 {
            if dict[value] == nil {
                dict[value] = 1
            }else {
                dict[value] = dict[value]! + 1
            }
        }
        
        
        var outputArray: Array<Int> = Array<Int>()
        
        for value in arr2 {
            
            if let count = dict[value] {
                for _ in 1...count{
                    outputArray.append(value)
                }
            }
        }
        
        let set2 = Set(arr2)
        
       var appendArray = Array<Int>()
        
        for value in arr1 {
            if !set2.contains(value) {
                appendArray.append(value)
            }
        }
        appendArray.sort()
        outputArray.append(contentsOf: appendArray)
        return outputArray        
    }
}

---

16ms

class Solution {
    func relativeSortArray(_ arr1: [Int], _ arr2: [Int]) -> [Int] {
        let (numToCount, numsNotInArr2) = getNumToCount(arr1, arr2)
        var result = [Int]()
        for num in arr2 {
            if let count = numToCount[num] {
                for _ in 0..<count {
                    result.append(num)
                }
            }
        }
        result.append(contentsOf: numsNotInArr2)
        return result
    }
    
    private func getNumToCount(_ arr1: [Int], _ arr2: [Int]) -> ([Int:Int], [Int]) {
        let arr2Set = Set(arr2)
        var numToCount = [Int:Int]()
        var numsNotInArr2 = [Int]()
        for num in arr1 {
            if !arr2Set.contains(num) {
                numsNotInArr2.append(num)
            } else {
                numToCount.updateValue((numToCount[num] ?? 0) + 1, forKey: num)
            }
        }
        numsNotInArr2 = numsNotInArr2.sorted()
        return (numToCount, numsNotInArr2)
    }
}

---

Runtime: 20 ms

Memory Usage: 21.2 MB

class Solution {
    func relativeSortArray(_ arr1: [Int], _ arr2: [Int]) -> [Int] {
        var arr1 = arr1.sorted(by:<)
        var n:Int = arr1.count
        var used:[Bool] = [Bool](repeating:false,count:n)
        var result:[Int] = [Int]()
        for x in arr2
        {
            for i in 0..<n
            {
                if arr1[i] == x && !used[i]
                {
                    result.append(x)
                    used[i] = true
                }
            }
        }
        for i in 0..<n
        {
            if !used[i]
            {
                result.append(arr1[i])
            }
        }
        return result
    }
}

---

20ms

class Solution {
  func relativeSortArray(_ arr1: [Int], _ arr2: [Int]) -> [Int] {

    var orderMap = [Int: Int]()

    for (offset, element) in arr2.enumerated() {
      orderMap[element] = offset
    }

    let result = arr1.sorted { left, right in
      switch (orderMap[left], orderMap[right]) {
      case (let leftOrder?, let rightOrder?):
        return leftOrder < rightOrder
      case (.none, .some):
        return false
      case (.some, .none):
        return true
      default:
        return left < right
      }
    }
    return result
  }
}

---

24ms

class Solution {
    func relativeSortArray(_ arr1: [Int], _ arr2: [Int]) -> [Int] {
        var counter = [Int : Int]()
        for num in arr1 {
            counter[num, default: 0] += 1
        }
        
        var ans = [Int]()
        for num in arr2 {
            ans += Array(repeating: num, count: counter[num]!)
            counter[num] = nil
        }
        
        let nums = counter.keys.sorted()
        for num in nums {
            ans += Array(repeating: num, count: counter[num]!)
            counter[num] = nil
        }
        
        return ans
    }
}

---

28ms

class Solution {
    func relativeSortArray(_ arr1: [Int], _ arr2: [Int]) -> [Int] {
        var dict = [Int: Int]()
        for i in 0..<arr2.count {
            dict[arr2[i]] = i
        }
        
        return arr1.sorted(by: { (e1, e2) in
            
            guard let idx1 = dict[e1] else {
                if dict[e2] == nil { return e1 < e2 }
                return false
            }
            guard let idx2 = dict[e2] else {
                return true
            }
            return idx1 < idx2
        })       
        
    }
}

---

52ms

class Solution {
  func relativeSortArray(_ arr1: [Int], _ arr2: [Int]) -> [Int] {
    var result = [Int]()
    var haystack = arr1
    for needle in arr2 {
      var index = 0
      for element in haystack {
        guard needle == element else { index += 1; continue }
        haystack.remove(at: index)
        result.append(element)
      }
    }
    result.append(contentsOf: haystack.sorted())
    return result
  }
}