题目描述

输入一个矩阵，按照从外向里以顺时针的顺序依次打印出每一个数字，例如，如果输入如下4 X 4矩阵： 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 则依次打印出数字1,2,3,4,8,12,16,15,14,13,9,5,6,7,11,10.

class Solution {
public:
    void printRound(vector<vector<int>>& matrix,int startrow,int startcol,
                       int endrow, int endcol,vector<int>& result)
    {
        for(int col = startcol; col <= endcol; col++)
        {
            result.push_back(matrix[startrow][col]);
        }
        
        if(startrow < endrow)
        {
            for(int row = startrow+1; row <= endrow; row++)
            {
                result.push_back(matrix[row][endcol]);
            }
            
            if(endcol > startcol)
            {
                for(int col = endcol-1; col >= startcol; col--)
                {
                    result.push_back(matrix[endrow][col]);
                }
            
                if(endrow - startrow > 1)
                {
                    for(int row = endrow-1; row > startrow; row--)
                    {
                        result.push_back(matrix[row][startcol]);
                    }
                }
            }
        } 
    }
        
    
    vector<int> printMatrix(vector<vector<int> > matrix) {
        int maxrow = matrix.size();
        int maxcol = matrix[0].size();
        
        int x = min(maxrow,maxcol);
        
        int maxround = x/2+x%2;
        vector<int> result;
        for(int round = 0; round < maxround; round++)
        {
            printRound(matrix,round,round,maxrow-round-1,maxcol-round-1,result);
        }
        return result;
    }
};