問題描述:
輸入一個矩陣,按照從外向裏以順時針的順序依次打印出每一個數字。
來源:力扣(LeetCode)
鏈接:https://leetcode-cn.com/problems/shun-shi-zhen-da-yin-ju-zhen-lcof
示例 1:
輸入:matrix = [[1,2,3],[4,5,6],[7,8,9]]
輸出:[1,2,3,6,9,8,7,4,5]
示例 2:
輸入:matrix = [[1,2,3,4],[5,6,7,8],[9,10,11,12]]
輸出:[1,2,3,4,8,12,11,10,9,5,6,7]
解題思路:
簡單題,注意邊界就行。
class Solution {
public:
vector<int> spiralOrder(vector<vector<int>>& matrix) {
vector<int> res;
if(matrix.empty()) return res;
int n = matrix.size();
int m = matrix[0].size();
int left=0,right=m-1,top=0,bot=n-1;
while(left<=right && top<=bot){
for(int i=left;i<=right;i++){
res.push_back(matrix[top][i]);
}
for(int i=top+1;i<=bot;i++){
res.push_back(matrix[i][right]);
}
if(top!=bot){
for(int i=right-1;i>=left;i--){
res.push_back(matrix[bot][i]);
}
}
if(left!=right){
for(int i=bot-1;i>top;i--){
res.push_back(matrix[i][left]);
}
}
left++,right--,top++,bot--;
}
return res;
}
};