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].
vector<int> fun(vector<vector<int> > &matrix){	vector<int> result;	int m = matrix.size();	int n = matrix[0].size();	int left = 0;	int right = n-1;	int top = 0;	int bottom = m-1;	while (left <= right && top <= bottom)	{		if (top <= bottom)		{			for (int i = left; i <= right; i++)			{				result.push_back(matrix[top][i]);			}			top++;		}				if (left <= right)		{			for (int i = top; i <= bottom; i++)			{				result.push_back(matrix[i][right]);			}			right--;		}		if (top <= bottom)		{			for (int i = right; i >= left; i--)			{				result.push_back(matrix[bottom][i]);			}			bottom--;		}		if (left <= right)		{			for (int i = bottom; i >= top; i--)			{				result.push_back(matrix[i][left]);			}			left++;		}	}	return result;}