题目链接:https://www.acwing.com/problem/content/description/39/
题目如下:
class Solution {
public:
vector<int> printMatrix(vector<vector<int> > matrix) {
vector<int> result;
if(matrix.size()==0) return result;
int row=matrix.size(),col=matrix[0].size();
vector<vector<bool>> visited(row,vector<bool>(col,false));//是否已被访问标记矩阵
int dx[4]={-1,0,1,0},dy[4]={0,1,0,-1};//顺时针定义四个方向
int x=0,y=0,d=1;//从左上角开始遍历,先往右走,走到底,再更改到下个方向,走完n^2个格子为止
for(int i=0;i<row*col;i++){
result.push_back(matrix[x][y]);
visited[x][y]=true;
int a=x+dx[d],b=y+dy[d];
if(a<0||a>=row||b<0||b>=col||visited[a][b]==true){
d=(d+1)%4;
a=x+dx[d],b=y+dy[d];
}
x=a,y=b;
}
return result;
}
};