feat: update solutions to lc problem: No.0054

No.0054.Spiral Matrix

Author: yanglbme

solution/0000-0099/0054.Spiral Matrix/README.md

@@ -50,19 +50,19 @@
 ```python
 class Solution:
     def spiralOrder(self, matrix: List[List[int]]) -> List[int]:
-        def add(i1, j1, i2, j2):
-            if i1 == i2:
-                return [matrix[i1][j] for j in range(j1, j2 + 1)]
-            if j1 == j2:
-                return [matrix[i][j1] for i in range(i1, i2 + 1)]
-            return [matrix[i1][j] for j in range(j1, j2)] + [matrix[i][j2] for i in range(i1, i2)] + [matrix[i2][j] for j in range(j2, j1, -1)] + [matrix[i][j1] for i in range(i2, i1, -1)]
         m, n = len(matrix), len(matrix[0])
-        i1, j1, i2, j2 = 0, 0, m - 1, n - 1
-        res = []
-        while i1 <= i2 and j1 <= j2:
-            res += add(i1, j1, i2, j2)
-            i1, j1, i2, j2 = i1 + 1, j1 + 1, i2 - 1, j2 - 1
-        return res
+        ans = []
+        top, bottom, left, right = 0, m - 1, 0, n - 1
+        while left <= right and top <= bottom:
+            ans.extend([matrix[top][j] for j in range(left, right + 1)])
+            ans.extend([matrix[i][right] for i in range(top + 1, bottom + 1)])
+            if left < right and top < bottom:
+                ans.extend([matrix[bottom][j]
+                           for j in range(right - 1, left - 1, -1)])
+                ans.extend([matrix[i][left]
+                           for i in range(bottom - 1, top, -1)])
+            top, bottom, left, right = top + 1, bottom - 1, left + 1, right - 1
+        return ans
 ```
 
 ### **Java**
@@ -71,44 +71,31 @@ class Solution:
 
 ```java
 class Solution {
-    private List<Integer> res;
-
     public List<Integer> spiralOrder(int[][] matrix) {
         int m = matrix.length, n = matrix[0].length;
-        res = new ArrayList<>();
-        int i1 = 0, i2 = m - 1;
-        int j1 = 0, j2 = n - 1;
-        while (i1 <= i2 && j1 <= j2) {
-            add(matrix, i1++, j1++, i2--, j2--);
-        }
-        return res;
-    }
-
-    private void add(int[][] matrix, int i1, int j1, int i2, int j2) {
-        if (i1 == i2) {
-            for (int j = j1; j <= j2; ++j) {
-                res.add(matrix[i1][j]);
+        int top = 0, bottom = m - 1, left = 0, right = n - 1;
+        List<Integer> ans = new ArrayList<>();
+        while (left <= right && top <= bottom) {
+            for (int j = left; j <= right; ++j) {
+                ans.add(matrix[top][j]);
             }
-            return;
-        }
-        if (j1 == j2) {
-            for (int i = i1; i <= i2; ++i) {
-                res.add(matrix[i][j1]);
+            for (int i = top + 1; i <= bottom; ++i) {
+                ans.add(matrix[i][right]);
             }
-            return;
-        }
-        for (int j = j1; j < j2; ++j) {
-            res.add(matrix[i1][j]);
-        }
-        for (int i = i1; i < i2; ++i) {
-            res.add(matrix[i][j2]);
-        }
-        for (int j = j2; j > j1; --j) {
-            res.add(matrix[i2][j]);
-        }
-        for (int i = i2; i > i1; --i) {
-            res.add(matrix[i][j1]);
+            if (left < right && top < bottom) {
+                for (int j = right - 1; j >= left; --j) {
+                    ans.add(matrix[bottom][j]);
+                }
+                for (int i = bottom - 1; i > top; --i) {
+                    ans.add(matrix[i][left]);
+                }
+            }
+            ++top;
+            --bottom;
+            ++left;
+            --right;
         }
+        return ans;
     }
 }
 ```
@@ -121,40 +108,35 @@ class Solution {
  * @return {number[]}
  */
 var spiralOrder = function (matrix) {
-    let m = matrix.length;
-    if (m === 0) return [];
-    let res = [];
-    let top = 0,
-        bottom = m - 1,
-        left = 0,
-        right = matrix[0].length - 1;
-    while (left < right && bottom > top) {
-        for (let i = left; i < right; i++) res.push(matrix[top][i]);
-        for (let i = top; i < bottom; i++) res.push(matrix[i][right]);
-        for (let i = right; i > left; i--) res.push(matrix[bottom][i]);
-        for (let i = bottom; i > top; i--) res.push(matrix[i][left]);
-        top++;
-        bottom--;
-        left++;
-        right--;
-    }
-    if (left === right) {
-        for (i = top; i <= bottom; i++) res.push(matrix[i][left]);
-    } else if (top === bottom) {
-        for (i = left; i <= right; i++) res.push(matrix[top][i]);
+    const m = matrix.length;
+    const n = matrix[0].length;
+    let [top, bottom, left, right] = [0, m - 1, 0, n - 1];
+    let ans = [];
+    while (top <= bottom && left <= right) {
+        for (let j = left; j <= right; ++j) {
+            ans.push(matrix[top][j]);
+        }
+        for (let i = top + 1; i <= bottom; ++i) {
+            ans.push(matrix[i][right]);
+        }
+        if (left < right && top < bottom) {
+            for (let j = right - 1; j >= left; --j) {
+                ans.push(matrix[bottom][j]);
+            }
+            for (let i = bottom - 1; i > top; --i) {
+                ans.push(matrix[i][left]);
+            }
+        }
+        [top, bottom, left, right] = [top + 1, bottom - 1, left + 1, right - 1];
     }
-    return res;
+    return ans;
 };
 ```
 
 ### **Go**
 
 ```go
 func spiralOrder(matrix [][]int) []int {
-	if len(matrix) == 0 {
-		return []int{}
-	}
-
 	m, n := len(matrix), len(matrix[0])
 	ans := make([]int, 0, m*n)
 
@@ -190,105 +172,64 @@ func spiralOrder(matrix [][]int) []int {
 class Solution {
 public:
     vector<int> spiralOrder(vector<vector<int>>& matrix) {
-        int row=matrix.size();
-        if(row==0)
+        int m = matrix.size(), n = matrix[0].size();
+        int top = 0, bottom = m - 1, left = 0, right = n - 1;
+        vector<int> ans;
+        while (top <= bottom && left <= right)
         {
-            vector<int> zero;
-            zero.clear();
-            return zero;
-        }
-        int col=matrix[0].size();
-        if(row==1)
-            return matrix[0];
-        if(col==0)
-        {
-            vector<int> zero;
-            zero.clear();
-            return zero;
-        }
-        if(col==1)
-        {
-            vector<int> temp;
-            for(int i=0;i<row;i++)
-                temp.push_back(matrix[i][0]);
-            return temp;
-        }
-        vector<int> result;
-        result=matrix[0];//result存储第一行
-        //temp=matirx.pop_back();
-        for(int i=1;i<matrix.size()-1;i++)
-        {
-            result.push_back(matrix[i][matrix[0].size()-1]);//存储每行最后一个
-        }
-        for(int i=0;i<col;i++)
-        {
-            result.push_back(matrix[row-1][col-1-i]);//倒序存储最后一行
-        }
-        for(int i=1;i<row-1;i++)
-        {
-            result.push_back(matrix[row-i-1][0]);//倒序存储每一行第一个
-            vector<int> zz(matrix[row-i-1].begin()+1,matrix[row-i-1].end()-1);//将中间行去除第一个和最后一个数
-            matrix[row-i-1]=zz;
+            for (int j = left; j <= right; ++j) ans.push_back(matrix[top][j]);
+            for (int i = top + 1; i <= bottom; ++i) ans.push_back(matrix[i][right]);
+            if (left < right && top < bottom)
+            {
+                for (int j = right - 1; j >= left; --j) ans.push_back(matrix[bottom][j]);
+                for (int i = bottom - 1; i > top; --i) ans.push_back(matrix[i][left]);
+            }
+            ++top;
+            --bottom;
+            ++left;
+            --right;
         }
-        vector<vector<int>> m2(matrix.begin()+1,matrix.end()-1);//将matrix去除第一行和最后一行，递归调用
-        //cout<<m2.size()<<"  "<<m2[0].size();
-        vector<int> l=spiralOrder(m2);
-        result.insert(result.end(),l.begin(),l.end());//将递归结果插入result后面
-        return result;
-        
+        return ans;
     }
 };
 ```
 
 ### **C#**
 
 ```cs
-using System;
-using System.Collections.Generic;
-
 public class Solution {
     public IList<int> SpiralOrder(int[][] matrix) {
-        var lenI = matrix.Length;
-        var lenJ = lenI == 0 ? 0 : matrix[0].Length;
-        var result = new List<int>(lenI * lenJ);
-        var rounds = (Math.Min(lenI, lenJ) + 1) / 2;
-        for (var r = 0; r < rounds; ++r)
+        int m = matrix.Length;
+        int n = matrix[0].Length;
+        int top = 0, bottom = m - 1, left = 0, right = n - 1;
+        var ans = new List<int>(m * n);
+        while (top <= bottom && left <= right)
         {
-            if (lenI - r * 2 == 1)
+            for (int j = left; j <= right; ++j)
             {
-                for (var j = r; j < lenJ - r; ++j)
-                {
-                    result.Add(matrix[r][j]);
-                }
+                ans.Add(matrix[top][j]);
             }
-            else if (lenJ - r * 2 == 1)
+            for (int i = top + 1; i <= bottom; ++i)
             {
-                for (var i = r; i < lenI - r; ++i)
-                {
-                    result.Add(matrix[i][r]);
-                }
+                ans.Add(matrix[i][right]);
             }
-            else
+            if (left < right && top < bottom)
             {
-                for (var j = r; j < lenJ - r - 1; ++j)
-                {
-                    result.Add(matrix[r][j]);
-                }
-                for (var i = r; i < lenI - r - 1; ++i)
-                {
-                    result.Add(matrix[i][lenJ - r - 1]);
-                }
-                for (var j = lenJ - r - 1; j > r; --j)
+                for (int j = right - 1; j >= left; --j)
                 {
-                    result.Add(matrix[lenI - r - 1][j]);
+                    ans.Add(matrix[bottom][j]);
                 }
-                for (var i = lenI - r - 1; i > r; --i)
+                for (int i = bottom - 1; i > top; --i)
                 {
-                    result.Add(matrix[i][r]);
+                    ans.Add(matrix[i][left]);
                 }
             }
+            ++top;
+            --bottom;
+            ++left;
+            --right;
         }
-        return result;
+        return ans;
     }
 }
 ```