LeetCode 刷题【58. 最后一个单词的长度、59. 螺旋矩阵 II】

58. 最后一个单词的长度

自己做

解：从后往前遍历

class Solution {
public:int lengthOfLastWord(string s) {int sum = 0;for(int i = (int)s.size() - 1; i >=  0; i--){if(s[i] != ' ')sum++;else if(sum != 0)break;}return sum;}
};

59. 螺旋矩阵 II

自己做

解：按边界螺旋填充

class Solution {
public:vector<vector<int>> generateMatrix(int n) {int num = 0;vector<vector<int>> res(n, vector<int>(n));//四个边界int top = 0;int bottom = n - 1;int left = 0;int right = n - 1;while(num <= n * n){//上边界：从左往右for(int i = left; i <= right; i++){num++;res[top][i] = num;}top++;if(num == n * n)            //旋转结束return res;//右边界：从上往下for(int i = top; i <= bottom; i++){num++;res[i][right] = num;}right--;if(num == n * n)            //旋转结束return res;//下边界：从右往左for(int i = right; i >= left; i--){num++;res[bottom][i] = num;}bottom--;if(num == n * n)            //旋转结束return res;//左边界：从下往上for(int i = bottom; i >= top; i--){num++;res[i][left] = num;}left++;if(num == n * n)            //旋转结束return res;}return res;}
};