顺时针打印矩阵

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.

思路：用左上和右下的坐标定位出一次要旋转打印的数据，一次旋转打印结束后，往对角分别前进和后退一个单位

class Solution {public:    vector<int> printMatrix(vector<vector<int> > matrix) {        int row = matrix.size(); //定义行数        int col = matrix[0].size();  //定义列数        vector<int> res;        if(row == 0 || col == 0)            return res; //返回空数组        int left = 0, right = col - 1, top = 0, bottom = row - 1;        while(left <= right && top <= bottom){            // left to right            for(int i = left; i <= right; i++)                res.push_back(matrix[top][i]);            //top to bottom            for(int i = top+1; i <= bottom; i++)                res.push_back(matrix[i][right]);            //right to left            for(int i = right - 1; i >= left && top < bottom; i--)                res.push_back(matrix[bottom][i]);            //bottom to top            for(int i = bottom - 1; i > top && right > left; i--)                res.push_back(matrix[i][left]);            left++; right--; top++; bottom--;        }        return res;    }};