Day109.cpp

// Spiral Order Matrix I

// https://www.interviewbit.com/problems/spiral-order-matrix-i/

vector<int> Solution::spiralOrder(const vector<vector<int> > &A) {
    
    int m = A.size();
    int n = A[0].size();
    vector<int> ans;

    int rs = 0, cs = 0;
    int re = m - 1;
    int ce = n - 1;

    while (rs <= re && cs <= ce) {
        // Traverse right
        for (int i = cs; i <= ce; i++) {
            ans.push_back(A[rs][i]);
        }
        rs++;

        // Traverse down
        for (int i = rs; i <= re; i++) {
            ans.push_back(A[i][ce]);
        }
        ce--;

        if (rs <= re) {
            // Traverse left
            for (int i = ce; i >= cs; i--) {
                ans.push_back(A[re][i]);
            }
            re--;
        }

        if (cs <= ce) {
            // Traverse up
            for (int i = re; i >= rs; i--) {
                ans.push_back(A[i][cs]);
            }
            cs++;
        }
    }

return ans;

}