代码随想录突击版刷题

704.二分查找

https://leetcode.cn/problems/binary-search/description/

 59.螺旋矩阵II

 https://leetcode.cn/problems/spiral-matrix-ii/description/、

参考题解写出

54.螺旋矩阵

 https://leetcode.cn/problems/spiral-matrix/description/

class Solution {
public:
    vector<int> spiralOrder(vector<vector<int>>& matrix) {
        int m = matrix.size();
        int n = matrix[0].size();
        int t = 0, l = 0, b = m - 1, r = n - 1;
        vector<int> ans;
        int num_size = m*n;
        while(num_size > 0){
            for(int i = l; i <= r && num_size > 0; i++){
                ans.push_back(matrix[t][i]);//从左到右
                num_size--;
            } 
            t++;
            for(int i = t; i <= b && num_size > 0; i++){// 从上到下
                ans.push_back(matrix[i][r]);
                num_size--;
            }
            r--;
            for(int i = r; i >= l && num_size > 0; i--){//从右到左
                ans.push_back(matrix[b][i]);
                num_size--;
            }
            b--;
            for(int i = b; i >= t && num_size > 0; i--){//从下到上
                ans.push_back(matrix[i][l]);
                num_size--;
            }
            l++;
        }
        return ans;
    }
};