模拟题,注意matrix只包含一行或者一列的情况,loop完之后还剩余一行或者一列的情况。

class Solution {
public:
    vector<int> spiralOrder(vector<vector<int> > &matrix) {
        vector<int> result{};
        if(matrix.empty()) return result;
        
        int m=matrix.size();
        int n=matrix[0].size();
        int loop=min(m,n)/2;
        int offset=1;
        int start_x{0},start_y{0},i{0},j{0};
        
        if(loop==0){
            for(auto x:matrix)
                for(auto xx:x)
                    result.push_back(xx);
            return result;
        }
        
        while(loop--){
            i=start_x;
            j=start_y;
            for(;j<start_y+n-offset;j++) result.push_back(matrix[i][j]);
            for(;i<start_x+m-offset;i++) result.push_back(matrix[i][j]);
            for(;j>start_y;j--) result.push_back(matrix[i][j]);
            for(;i>start_x;i--) result.push_back(matrix[i][j]);
            start_x++;
            start_y++;
            offset+=2;
        }
        if(min(m,n)%2!=0 && min(m,n)==m){
            i=start_x;
            j=start_y;
            for(;j<=start_y+n-offset;j++) result.push_back(matrix[i][j]);
        }
        else if(min(m,n)%2!=0 && min(m,n)==n){
            i=start_x;
            j=start_y;
            for(;i<=start_x+m-offset;i++) result.push_back(matrix[i][j]);
        }
        return result;
    }
};