leetcode

0 class Solution {

1 public:

2 bool valid(int i, int m, int j, int n) { return i >= 0 && i <= m && j >= 0 && j <= n; }

3

4 void quick_adjust(int &i, int &j, bool &up) {

5 if (up)

6 i++;

7 else

8 j++;

9 up = !up;

10 }

11

12 void move(int &i, int &j, bool &up) {

13 if (up) {

14 i--;

15 j++;

16 } else {

17 i++;

18 j--;

19 }

20 }

21

22 vector<int> findDiagonalOrder(vector<vector<int>> &mat) {

23 vector<int> res;

24 bool up = true;

25 int i = 0, j = 0;

26 int m = mat.size() - 1, n = mat[0].size() - 1;

27

28 while (true) {

29 res.push_back(mat[i][j]);

30 if (i == m && j == n) break;

31

32 move(i, j, up);

33

34 if (!valid(i, m, j, n)) {

35 quick_adjust(i, j, up);

36 while (!valid(i, m, j, n))

37 move(i, j, up);

38 }

39 }

40

41 return res;

42 }

43 };