54.螺旋矩阵（中）/59.螺旋矩阵Ⅱ（中）

目录

• 54.题目
• python
  • 模拟
• JavaScript
  • 按层模拟
• 59.题目
• 模拟

54.题目

python

模拟

class Solution:
    def spiralOrder(self, matrix: List[List[int]]) -> List[int]:
        m, n = len(matrix), len(matrix[0])
        res = []
        top, bottom = 0, m - 1
        left, right = 0, n - 1
        while top <= bottom and left <= right:
            # 遍历上边界
            for i in range(left, right + 1):
                res.append(matrix[top][i])
            top += 1
            # 遍历右边界
            for i in range(top, bottom + 1):
                res.append(matrix[i][right])
            right -= 1
            # 遍历下边界
            if top <= bottom:
                for i in range(right, left - 1, -1):
                    res.append(matrix[bottom][i])
                bottom -= 1
            # 遍历左边界
            if left <= right:
                for i in range(bottom, top - 1, -1):
                    res.append(matrix[i][left])
                left += 1
        return res

JavaScript

按层模拟

var spiralOrder = function(matrix) {
    if (!matrix.length || !matrix[0].length) {
        return [];
    }

    const rows = matrix.length, columns = matrix[0].length;
    const order = []; //结果数组
    let left = 0, right = columns - 1, top = 0, bottom = rows - 1;
    while (left <= right && top <= bottom) {
        for (let column = left; column <= right; column++) {//左到右
            order.push(matrix[top][column]);
        }
        for (let row = top + 1; row <= bottom; row++) {//上到下
            order.push(matrix[row][right]);
        }
        if (left < right && top < bottom) {
            for (let column = right - 1; column > left; column--) {//右到左
                order.push(matrix[bottom][column]);
            }
            for (let row = bottom; row > top; row--) {//下到上
                order.push(matrix[row][left]);
            }
        }
        //外面一圈遍历完后，向内收缩指针
        [left, right, top, bottom] = [left + 1, right - 1, top + 1, bottom - 1];
    }
    return order;
};

59.题目

模拟

class Solution:
    def generateMatrix(self,n: int) -> List[List[int]]:
        matrix = [[0] * n for _ in range(n)]
        num = 1
        top, bottom = 0, n - 1
        left, right = 0, n - 1
        while num <= n * n:
            # Traverse top row
            for i in range(left, right + 1):
                matrix[top][i] = num
                num += 1
            top += 1
            # Traverse right column
            for i in range(top, bottom + 1):
                matrix[i][right] = num
                num += 1
            right -= 1
            # Traverse bottom row
            for i in range(right, left - 1, -1):
                matrix[bottom][i] = num
                num += 1
            bottom -= 1
            # Traverse left column
            for i in range(bottom, top - 1, -1):
                matrix[i][left] = num
                num += 1
            left += 1
        return matrix