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]
.
class Solution {
public:
vector<int> spiralOrder(vector<vector<int> > &matrix) {
vector<int> result;
if (matrix.size() == 0)
{
return result;
}
int left = 0;
int top = 0;
int bottom = matrix.size() - 1;
int right = matrix[0].size() - 1;
int row = 0;
int column = 0;
while (left <= right && top <= bottom)
{
if (column <= right)
{
while (column <= right)
{
result.push_back(matrix[row][column]);
column++;
}
column--;
top++;
row++;
}
if (left <= right && top <= bottom && row <= bottom)
{
while (row <= bottom)
{
result.push_back(matrix[row][column]);
row++;
}
row--;
right--;
column--;
}
if (left <= right && top <= bottom && column >= left)
{
while (column >= left)
{
result.push_back(matrix[row][column]);
column--;
}
column++;
bottom--;
row--;
}
if (left <= right && top <= bottom && row >= top)
{
while (row >= top)
{
result.push_back(matrix[row][column]);
row--;
}
row++;
left++;
column++;
}
}
return result;
}
};