Given a matrix of m x n elements (m rows, n columns), return all elements of the matrix in spiral order.
For example,
Given the following matrix:
[ [ 1, 2, 3 ], [ 4, 5, 6 ], [ 7, 8, 9 ] ]
You should return [1,2,3,6,9,8,7,4,5].
只适合方阵的C++实现代码：
vector<int> spiralOrder(vector<vector<int> > &matrix) { if(matrix.empty()||matrix[0].empty()) return vector<int>(); vector<int> ret; int n=matrix.size(); int count=n*n; int i=0; int j=0; while(count) { if(count==1) { ret.push_back(matrix[i][j]); break; } for(; j<n-i-1; j++) { ret.push_back(matrix[i][j]); count--; } for(; i<j; i++) { ret.push_back(matrix[i][j]); count--; } for(; j>n-i-1; j--) { ret.push_back(matrix[i][j]); count--; } for(; i>j; i--) { ret.push_back(matrix[i][j]); count--; } i++; j++; } return ret; }
原文：http://www.cnblogs.com/wuchanming/p/4111548.html