LeetCode – Refresh – Spiral Matrix

When finally check the middle line, it is checking whether the min(n, m) is odd or even number.

class Solution {
public:
    vector<int> spiralOrder(vector<vector<int> > &matrix) {
        vector<int> result;
        if (matrix.size() == 0) return result;
        int n = matrix.size(), m = matrix[0].size(), rec = min(n, m)/2;
        for (int i = 0; i < rec; i++) {
            for (int j = i; j < m-i-1; j++) result.push_back(matrix[i][j]);
            for (int j = i; j < n-i-1; j++) result.push_back(matrix[j][m-i-1]);
            for (int j = m-i-1; j > i; j--) result.push_back(matrix[n-i-1][j]);
            for (int j = n-i-1; j > i; j--) result.push_back(matrix[j][i]);
        }
        if (rec*2 != min(m, n)) {
            if (n > m) {
                for (int i = rec; i <= n-rec-1; i++) result.push_back(matrix[i][m/2]);
            } else {
                for (int i = rec; i <= m-rec-1; i++) result.push_back(matrix[n/2][i]);
            }
        }
        return result;
    }
};