54. Spiral Matrix-蒲公英云

54. Spiral Matrix

My Submissions

Question

Total Accepted: 52570 Total Submissions: 238571 Difficulty: Medium

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].

我的代码如下：效率不是很高，注意下面红色部分的判断

<span style="color:#333333;">class Solution {
public:
    vector<int> spiralOrder(vector<vector<int>>& matrix) {
        vector<int>res;
        if(!matrix.size())return res;
        int row = matrix.size();
        int col = matrix[0].size();
        int temp1 = row%2;
        if(row==1)return matrix[0];
        if(col==1){
            for(int i=0;i<row;i++){
                res.push_back(matrix[i][0]);
            }
            return res;
        }
        spiral(res, matrix, row-1,col-1,0);
        return res;
    }
    void spiral(vector<int>&res, vector<vector<int>>&matrix,int row,int col, int begin){
        if(row>0&&col>0){
            int curRow = begin;
            int curCol = begin;
            </span><span style="color:#cc0000;">if(col==begin) {
               for(;curRow <= row;curRow++) {
                   res.push_back(matrix[curRow][begin]);
               }
               return;
           }</span><span style="color:#333333;">
            for(;curCol < col;curCol++){
                res.push_back(matrix[curRow][curCol]);
            }
            for(;curRow<row;curRow++){
                res.push_back(matrix[curRow][curCol]);
            }
            for(;curCol>begin;curCol--){
                res.push_back(matrix[curRow][curCol]);
            }
            for(;curRow>begin;curRow--){
                res.push_back(matrix[curRow][curCol]);
            }
            spiral(res, matrix,row-1,col-1,begin+1);
        }else {
            return;
        }
    }
};</span>