[Swift]LeetCode989. 數組形式的整數加法 | Add to Array-Form of Integer

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For a non-negative integer X, the array-form of X is an array of its digits in left to right order.  For example, if X = 1231, then the array form is [1,2,3,1].

Given the array-form A of a non-negative integer X, return the array-form of the integer X+K.

Example 1:

Input: A = [1,2,0,0], K = 34
Output: [1,2,3,4] Explanation: 1200 + 34 = 1234 

Example 2:

Input: A = [2,7,4], K = 181 Output: [4,5,5] Explanation: 274 + 181 = 455 

Example 3:

Input: A = [2,1,5], K = 806 Output: [1,0,2,1] Explanation: 215 + 806 = 1021 

Example 4:

Input: A = [9,9,9,9,9,9,9,9,9,9], K = 1 Output: [1,0,0,0,0,0,0,0,0,0,0] Explanation: 9999999999 + 1 = 10000000000

Note：

1. 1 <= A.length <= 10000
2. 0 <= A[i] <= 9
3. 0 <= K <= 10000
4. If A.length > 1, then A[0] != 0

---

對於非負整數 X 而言，X 的數組形式是每位數字按從左到右的順序造成的數組。例如，若是 X = 1231，那麼其數組形式爲 [1,2,3,1]。

給定非負整數 X 的數組形式 A，返回整數 X+K 的數組形式。 

示例 1：

輸入：A = [1,2,0,0], K = 34
輸出：[1,2,3,4]
解釋：1200 + 34 = 1234

解釋 2：

輸入：A = [2,7,4], K = 181
輸出：[4,5,5]
解釋：274 + 181 = 455

示例 3：

輸入：A = [2,1,5], K = 806
輸出：[1,0,2,1]
解釋：215 + 806 = 1021

示例 4：

輸入：A = [9,9,9,9,9,9,9,9,9,9], K = 1
輸出：[1,0,0,0,0,0,0,0,0,0,0]
解釋：9999999999 + 1 = 10000000000

提示：

1. 1 <= A.length <= 10000
2. 0 <= A[i] <= 9
3. 0 <= K <= 10000
4. 若是 A.length > 1，那麼 A[0] != 0

---

312ms

 1 class Solution {
 2     
 3     func addToArrayForm(_ A: [Int], _ K: Int) -> [Int] {
 4         let kDigits = digits(K)
 5         let result = add(A, kDigits)
 6         return result
 7     }
 8 
 9     func digits(_ value: Int) -> [Int] {
10         var result = [Int]()
11 
12         var value = value
13         while value > 0 {
14             result.append(value%10)
15             value /= 10
16         }
17 
18         return result.reversed()
19     }
20 
21     func add(_ values1: [Int], _ values2: [Int]) -> [Int] {
22         var result = [Int]()
23         var index1 = values1.count - 1
24         var index2 = values2.count - 1
25         var carry = 0
26 
27         while index1 >= 0 || index2 >= 0 || carry > 0 {
28             let value1 = (index1 >= 0) ? values1[index1] : 0
29             let value2 = (index2 >= 0) ? values2[index2] : 0
30             let sum = value1 + value2 + carry
31             result.append(sum%10)
32             carry = sum / 10
33 
34             index1 -= 1
35             index2 -= 1
36         }
37 
38         return result.reversed()
39     }
40 }

---

316ms

 1 class Solution {
 2     func addToArrayForm(_ A: [Int], _ K: Int) -> [Int] {
 3         var output: [Int] = []
 4         var current: Int = 0
 5         var kTmp: Int = K
 6     
 7         var i: Int = A.count - 1
 8         while i >= 0 || kTmp > 0 {
 9             if i >= 0 {
10                 current += A[i]
11             }
12             if kTmp > 0 {
13                 current += kTmp % 10
14                 kTmp /= 10
15             }
16             output.append(current % 10)
17             current /= 10
18             i -= 1
19         }
20         if current > 0 {
21             output.append(current)
22         }
23         output.reverse()
24         return output
25     }
26 }

---

324ms

 1 class Solution {
 2 func addToArrayForm(_ A: [Int], _ K: Int) -> [Int] {
 3     guard K != 0 else {
 4         return A
 5     }
 6     let ka = String(K).compactMap {Int("\($0)")}
 7     
 8     guard A.count != 0 else {
 9         return ka
10     }
11     
12     let add: [Int]
13     var result: [Int]
14     if ka.count < A.count {
15         add = Array(ka.reversed())
16         result = Array(A.reversed())
17     } else {
18         add = Array(A.reversed())
19         result = Array(ka.reversed())
20     }
21     var acc = 0
22     var index = 0
23     while (acc > 0) || (index < add.count) {
24         let s1 = index < add.count ? add[index] : 0
25         let s2 = index < result.count ? result[index] : 0
26         let sum = s1 + s2 + acc
27         acc = sum / 10
28         if index < result.count {
29             result[index] = sum % 10
30         } else {
31             result.append(sum % 10)
32         }
33         index += 1
34     }
35     return result.reversed()
36  }
37 }

---

336ms

 1 class Solution {
 2     func addToArrayForm(_ A: [Int], _ K: Int) -> [Int] {
 3         var A = A
 4         var n:Int = A.count
 5         var c:Int = K
 6         for i in stride(from:A.count - 1,through:0,by:-1)
 7         {
 8             A[i] += c
 9             c = A[i] / 10
10             A[i] %= 10          
11         }
12         var ret:[Int] = [Int]()
13         while(c > 0)
14         {
15             ret.insert(c%10,at:0)
16             c /= 10
17         }
18         for v in A
19         {
20             ret.append(v)
21         }
22         return ret
23     }
24 }

---

340ms

 1 class Solution {
 2   private func IntToArra(_ num: Int) -> [Int] {
 3     var kArr = [Int]()
 4     var p = 10
 5     while true {
 6       kArr.append(num % p / (p / 10) )
 7       if num % p == num { break }
 8       p *= 10
 9     }
10     return kArr
11   }
12 
13   private func longPlus(_ a: [Int], _ b: [Int]) -> [Int] {
14     let maxA, minA: [Int]
15     (maxA, minA) = a.count >= b.count ? (a, b) : (b, a)
16     var inc: Int = 0
17     var res = [Int](repeating: 0, count: maxA.count + 1)
18     for i in stride(from: maxA.count, through: 0, by: -1) {
19       let maxInd = i - 1
20       let minInd = i - (maxA.count - minA.count) - 1
21       let maxVal = maxInd >= 0 ? maxA[maxInd] : 0
22       let minVal = minInd >= 0 ? minA[minInd] : 0
23       let sum = maxVal + minVal + inc
24       if sum >= 10 {
25         res[i] = sum % 10
26         inc = 1
27       } else {
28         res[i] = sum
29         inc = 0
30       }
31     }
32     if res[0] == 0 {
33       return Array(res[1..<res.count])
34     }
35     return res
36   }
37   
38   func addToArrayForm(_ A: [Int], _ K: Int) -> [Int] {
39     return longPlus(A, IntToArra(K).reversed()) //fix
40   }
41 }

---

376ms

 1 class Solution {
 2     func addToArrayForm(_ A: [Int], _ K: Int) -> [Int] {
 3         var a = A
 4         var k = K
 5         
 6         var i = 0
 7         var carry = 0
 8         
 9         while i < a.count || k > 0 {
10             var ai = 0, bi = 0
11             var aIndex = -1
12             
13             if i < a.count {
14                 aIndex = a.count - (i + 1)
15                 ai = a[aIndex]
16             }
17             if k > 0 {
18                 bi = k > 9 ? k % 10 : k
19             }
20             
21             let c = ai + bi + carry
22             carry = c / 10
23             
24             if c > 9 {
25                 if aIndex >= 0 {
26                     a[aIndex] = c % 10
27                 } else {
28                     a.insert(c % 10, at: 0)
29                 }
30 
31             } else {
32                 if aIndex >= 0 {
33                     a[aIndex] = c
34                 } else {
35                     a.insert(c, at: 0)
36                 }
37             }
38             
39             i += 1
40             k /= 10
41         }
42         
43         if carry > 0 {
44             a.insert(carry, at: 0)
45         }
46 
47         return a
48         
49     }
50 }

---

408ms

 1 class Solution {
 2     func addToArrayForm(_ A: [Int], _ K: Int) -> [Int] {
 3         var aIndex = A.count - 1
 4         var k = K
 5         var c = 0
 6         var result = [Int]()
 7         while (aIndex > -1 || k > 0 || c > 0) {
 8             var sum = c
 9             if aIndex > -1 {
10                 sum += A[aIndex]
11                 aIndex -= 1
12             }
13             
14             if k > 0 {
15                 sum += k % 10
16                 k = k / 10
17             }
18             
19             c = sum / 10
20             result.insert(sum%10, at: 0)
21         }
22         
23         return result
24     }
25 }