顺时针打印二维数组，以前在牛客网上做过，不过还是忘了

 int n,m;
    vector<vector<bool> > v;
    bool judge(int i,int j)
    {
       return i>=0 && i<n && j>=0 && j<m && !v[i][j];    //判断，相当于小旗子 右，下，左，上
    }
public:
    vector<int> printMatrix(vector<vector<int> > matrix) {
        vector<int> res;
        if( !(n = matrix.size()) || !(m = matrix[0].size()))
           return res;
        v = vector<vector<bool> >(n,vector<bool>(m,false)); //如何定义二维数组！
        const int D[4][2] = {{0,1},{1,0},{0,-1},{-1,0}}; //四个方向
        int i = 0, j = 0, d = 0, T = m * n;
        while(T--){
            res.push_back(matrix[i][j]);
            v[i][j] = true;
            if(!judge(i + D[d][0], j + D[d][1])) (++d) %= 4; //转弯
            i += D[d][0], j += D[d][1];//前进
        }
        return res;
    }

　　Spiral Matrix II

class Solution {
    vector<vector<bool>> v;
public:
    vector<vector<int>> generateMatrix(int n) {
        vector<vector<int>> res=vector<vector<int> >(n,vector<int>(n)); 
        v=vector<vector<bool>>(n,vector<bool>(n,false));
        int num=n*n;
        if(num == 0)
            return res;
        int i=0;
        int row=0,col=0;
        int D[4][2]={{0,1},{1,0},{0,-1},{-1,0}};
        int d=0;
        while(++i<=num)
        {
            res[row][col]=i;
            v[row][col]=true;
            if(!judge(n,row+D[d][0],col+D[d][1])) //if(row<0 || row>=n || col<0 || col>=n || v[row][col]) 这么写为什么不对
                (++d) %= 4;
            row +=D[d][0],col+=D[d][1];
        }
        return res;
    }
    bool judge(int n,int row,int col)
    {
        return row>=0 && row<n && col>=0 && col<n && !v[row][col];
    }
};