Given an integer n, generate a square matrix filled with elements from 1 to n2 in spiral order.
For example,
Given n = 3,
You should return the following matrix:
[
[ 1, 2, 3 ],
[ 8, 9, 4 ],
[ 7, 6, 5 ]
]
解题思路：
参考Java for LeetCode 054 Spiral Matrix，修改下代码即可，JAVA实现如下：
static public int[][] generateMatrix(int n) {
if(n==0)
return new int[0][0];
int[][] matrix=new int[n][n];
int num=0,left = 0, right = matrix[0].length - 1, up = 0, down = matrix.length - 1;
while (left <= right && up <= down) {
for (int i = left; i <= right&&up<=down; i++)
matrix[up][i]=++num;
up++;
for (int i = up; i <= down&&left<=right; i++)
matrix[i][right]=++num;
right--;
for (int i = right; i >= left&&up<=down; i--)
matrix[down][i]=++num;
down--;
for (int i = down; i >= up&&left<=right; i--)
matrix[i][left]=++num;
left++;
}
return matrix;
}
Java for LeetCode 059 Spiral Matrix II
原文：http://www.cnblogs.com/tonyluis/p/4506737.html