Given a positive integer n, generate a square matrix filled with elements from 1 to n2 in spiral order.
Example:
Input: 3 Output: [ [ 1, 2, 3 ], [ 8, 9, 4 ], [ 7, 6, 5 ] ]
给定一个正整数 n，生成一个包含 1 到 n2 所有元素，且元素按顺时针顺序螺旋排列的正方形矩阵。
示例:
输入: 3 输出: [ [ 1, 2, 3 ], [ 8, 9, 4 ], [ 7, 6, 5 ] ]
8ms
1 class Solution {
2 func generateMatrix(_ n: Int) -> [[Int]] {
3 if n == 0 {
4 return [[Int]]();
5 }
6 var i = 0, j = 0;
7 var result = [[Int]]()
8 let m = n
9 var minI = -1, minJ = -1, maxI = m, maxJ = n;
10
11 let maxLength = m * n
12
13 var tempArray = [Int]()
14 for i in 0 ..< maxLength {
15 if tempArray.count == n {
16 result.append(tempArray)
17 tempArray.removeAll()
18 tempArray.append(i)
19 } else {
20 tempArray.append(i)
21 }
22 }
23 result.append(tempArray)
24
25 //action: 0: i+, 1: j+, 2: i-, 3: j-
26 var action = 1
27 var value = 1
28
29
30 while value <= maxLength {
31 switch action {
32 case 0: do {
33 while i < maxI {
34 result[i][j] = value
35 value += 1
36 i += 1
37 }
38 i -= 1
39 maxJ -= 1
40
41 action = 3
42 j -= 1
43 }
44 break;
45 case 1: do {
46 while j < maxJ {
47 result[i][j] = value
48 value += 1
49 j += 1
50 }
51 j -= 1
52 minI += 1
53
54 action = 0
55 i += 1
56 }
57 break;
58 case 2: do {
59 while i > minI {
60 result[i][j] = value
61 value += 1
62 i -= 1
63 }
64 i += 1
65 minJ += 1
66
67 action = 1
68 j += 1
69 }
70 break;
71 case 3: do {
72 while j > minJ {
73 result[i][j] = value
74 value += 1
75 j -= 1
76 }
77 j += 1
78 maxI -= 1
79
80 action = 2
81 i -= 1
82 }
83 break;
84 default:
85 break
86 }
87 }
88 return result;
89 }
90 }
12ms
1 class Solution {
2 func generateMatrix(_ n: Int) -> [[Int]] {
3 let iterations = n / 2 + n % 2
4 var arr = Array(repeating: (Array(repeating: 0, count: n)), count: n)
5 var value = 0
6 var count = n
7 var isIterating = false
8 for index in 0..<iterations {
9 var j = index
10 var i = index
11
12
13
14 while (j < count) {
15 value += 1
16 arr[i][j] = value
17 j += 1
18 isIterating = true
19 }
20 j -= 1
21
22 i += 1
23 while (i < count) {
24 value += 1
25 arr[i][j] = value
26 i += 1
27 isIterating = true
28 }
29 i -= 1
30
31 j -= 1
32
33 if !isIterating { break }
34
35 while(j >= index) {
36 value += 1
37 arr[i][j] = value
38 j -= 1
39 }
40 j += 1
41
42 i -= 1
43
44 while(i > index) {
45 value += 1
46 arr[i][j] = value
47 i -= 1
48 }
49
50 count -= 1
51
52 isIterating = false
53 }
54
55 return arr
56 }
57 }
12ms
1 class Solution {
2 func generateMatrix(_ n: Int) -> [[Int]] {
3 guard n > 0 else {
4 return [[Int]]()
5 }
6
7 var num = 1
8 var res = Array(repeating: Array(repeating: 0, count: n), count: n)
9
10 for layer in 0..<n / 2 {
11 let start = layer
12 let end = n - layer - 1
13
14 // top
15 for i in start..<end {
16 res[start][i] = num
17 num += 1
18 }
19
20 // right
21 for i in start..<end {
22 res[i][end] = num
23 num += 1
24 }
25
26 // bottom
27 for i in stride(from: end, to: start, by: -1) {
28 res[end][i] = num
29 num += 1
30 }
31
32 // left
33 for i in stride(from: end, to: start, by: -1) {
34 res[i][start] = num
35 num += 1
36 }
37 }
38
39 // handle the center one
40 if n % 2 != 0 {
41 res[n / 2][n / 2] = n * n
42 }
43
44 return res
45 }
46 }
16ms
1 class Solution {
2 func generateMatrix(_ n: Int) -> [[Int]] {
3 var n = n
4 var result = Array<[Int]>(repeating: Array<Int>(repeating: 0, count: n), count: n)
5 var i = 1
6 let max = n * n
7 var x = 0, y = 0
8 while i <= max {
9 while y < n && result[x][y] == 0 { //向右
10 result[x][y] = i
11 i += 1
12 y += 1
13 }
14 x += 1
15 y -= 1
16 while x < n && result[x][y] == 0 { //向下
17 result[x][y] = i
18 i += 1
19 x += 1
20 }
21 x -= 1
22 y -= 1
23 while y >= 0 && result[x][y] == 0 { //向左
24 result[x][y] = i
25 i += 1
26 y -= 1
27 }
28 y += 1
29 x -= 1
30 while x >= 0 && result[x][y] == 0 { //向上
31 result[x][y] = i
32 i += 1
33 x -= 1
34 }
35 x += 1
36 y += 1
37 n -= 1
38 }
39 return result
40 }
41 }
16ms
1 class Solution {
2 func generateMatrix(_ n: Int) -> [[Int]] {
3
4 var minRow = 0, maxRow = n - 1, minCol = 0, maxCol = n - 1
5 var result = [[Int]](repeating: [Int](repeating: 0, count: n), count: n)
6
7 var num = 0
8 while true {
9 for j in minCol...maxCol {
10 num += 1
11 result[minRow][j] = num
12 }
13 minRow += 1
14 if num == n * n { break }
15
16 for i in minRow...maxRow {
17 num += 1
18 result[i][maxCol] = num
19 }
20 maxCol -= 1
21 if num == n * n { break }
22
23 for j in (minCol...maxCol).reversed() {
24 num += 1
25 result[maxRow][j] = num
26 }
27 maxRow -= 1
28 if num == n * n { break }
29
30 for i in (minRow...maxRow).reversed() {
31 num += 1
32 result[i][minCol] = num
33 }
34 minCol += 1
35 if num == n * n { break }
36 }
37
38 return result
39
40 }
41 }
20ms
1 class Solution {
2 func generateMatrix(_ n: Int) -> [[Int]] {
3 var res = [[Int]](repeating: [Int](repeating: 0, count: n), count: n)
4 var k = 1
5 for i in 0..<(n/2){//圈数
6 for y in i..<(n-i){
7 res[i][y] = k
8 k += 1
9 }
10 for x in (i+1)..<(n-1-i){
11 res[x][n-1-i] = k
12 k += 1
13 }
14 for y in i..<(n-i){
15 res[n-1-i][n-1-y] = k
16 k += 1
17 }
18 for x in (i+1)..<(n-1-i){
19 res[n-1-x][i] = k
20 k += 1
21 }
22 }
23 if n % 2 != 0{
24 res[n/2][n/2] = k
25 }
26 return res
27 }
28 }
原文地址：https://www.cnblogs.com/strengthen/p/9920694.html
时间： 2024-10-17 12:16:56