标签：style blog color 使用 io for ar div log
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 ]
]
思路：使用for循环依次向右、向下、向左、向上设置矩阵对应位置的值。注意边界条件。
1 class Solution { 2 public: 3 vector<vector<int>> generateMatrix( int n ) { 4 vector<vector<int>> matrix( n, vector<int>( n, 0 ) ); 5 int val = 1; 6 for( int step = 0; step < (n+1)/2; ++step ) { 7 for( int j = step; j < n-step; ++j ) { 8 matrix[step][j] = val++; 9 } 10 for( int i = step+1; i < n-step; ++i ) { 11 matrix[i][n-step-1] = val++; 12 } 13 for( int j = n-step-2; j >= step; --j ) { 14 matrix[n-step-1][j] = val++; 15 } 16 for( int i = n-step-2; i > step; --i ) { 17 matrix[i][step] = val++; 18 } 19 } 20 return matrix; 21 } 22 };
标签：style blog color 使用 io for ar div log
原文地址：http://www.cnblogs.com/moderate-fish/p/3936018.html
