🌵59. Spiral Matrix II
https://leetcode.com/problems/spiral-matrix-ii/
js
/**
* @param {number} n
* @return {number[][]}
*/
var generateMatrix = function(n) {
var matrix = []
for (let i = 0; i < n; i++) {
matrix[i] = []
}
var top = 0
var bottom = n - 1
var left = 0
var right = n - 1
var num = 1
while (num <= n * n) {
for (let i = left; i <= right; i++) {
matrix[top][i] = num++
}
top++
for (let i = top; i <= bottom; i++) {
matrix[i][right] = num++
}
right--
for (let i = right; i >= left; i--) {
matrix[bottom][i] = num++
}
bottom--
for (let i = bottom; i >= top; i--) {
matrix[i][left] = num++
}
left++
}
return matrix
}py
class Solution(object):
def generateMatrix(self, n):
"""
:type n: int
:rtype: List[List[int]]
"""
matrix = [[0 for i in range(n)] for j in range(n)]
top, bottom, left, right = 0, n - 1, 0, n - 1
num = 1
while num <= n * n:
for i in range(left, right + 1):
matrix[top][i] = num
num += 1
top += 1
for i in range(top, bottom + 1):
matrix[i][right] = num
num += 1
right -= 1
for i in range(right, left - 1, -1):
matrix[bottom][i] = num
num += 1
bottom -= 1
for i in range(bottom, top - 1, -1):
matrix[i][left] = num
num += 1
left += 1
return matrix