top145-#54

[LionCoder4ever]

• used array store the visited node,
• take care of the corner case when input like [[1],[2],[3],[4],[5],[6],[7],[8],[9]], m=9, n = 1, "no2","no4" loop may out of index

class Solution {
public:
    vector<int> spiralOrder(vector<vector<int>>& matrix) {
        int m = matrix.size();
        int n = matrix[0].size();
        bool used[m][n];
        for(int i=0;i<m;i++)
            for(int j=0;j<n;j++)
                used[i][j] =false;

        vector<int> ans(0);
        for(int i = 0;i<m;i++) {
            for(int j =i;j<n-i;j++) {
                if (used[i][j]) break;
                used[i][j] = true;
                cout << "1==" << matrix[i][j] << endl;
                ans.push_back(matrix[i][j]); 
            }
            for(int j=i+1;j<m-i-1 && (n-i-1 >= 0) ;j++) {
                if (used[j][n-i-1]) break;
                used[j][n-i-1] = true;
                cout << "2==" << matrix[j][n-i-1] << endl;
                ans.push_back(matrix[j][n-i-1]);
            }
            for(int j =n-i-1;j>=i;j--) {
                if (used[m-i-1][j]) break;
                used[m-i-1][j] = true;
                cout << "3==" << matrix[m-i-1][j] << endl;
                ans.push_back(matrix[m-i-1][j]); 
            }
            for(int j =m-i-2;j>=i+1 && (i < n);j--) {
                if (used[j][i]) break;
                used[j][i] =true;
                cout << "4==" << matrix[j][i] << endl;
                ans.push_back(matrix[j][i]); 
            }
        }
        return ans;
    }
};