题目描述
Given a matrix of m x n elements (m rows, n columns), return all elements of the matrix in spiral order.
Example1:
Input: [ [ 1, 2, 3 ], [ 4, 5, 6 ], [ 7, 8, 9 ] ] Output: [1,2,3,6,9,8,7,4,5]
Note:
You may assume all input has valid answer.
解题思路
- 循环的条件要记得 cycle = (min(row, col) - 1) / 2 + 1
-
最后两个防止重复的要记得 row - i - 1 != i col - i - 1 != i - 记得将matrix[i][j] // 下标换成对应的
class Solution {
public:
vector<int> spiralOrder(vector<vector<int>>& matrix) {
int row = matrix.size();
vector<int> res;
if(row == 0){
return res;
}
int col = matrix[0].size();
if(row == 1 && col == 1){
res.push_back(matrix[0][0]);
return res;
}
int cycle = (min(row, col) - 1) / 2 + 1;
for(int i = 0; i < cycle; i++){
for(int j = i; j < col - i; j++){
res.push_back(matrix[i][j]);
}
for(int j = i + 1; j < row - i; j++){
res.push_back(matrix[j][col - 1 - i]);
}
for(int j = col - i - 2; j >= i && row - 1 - i != i; j--){
res.push_back(matrix[row - i - 1][j]);
}
for(int j = row - i - 2; j > i && col - 1 - i != i; j--){
res.push_back(matrix[j][i]);
}
}
return res;
}
};
