leetcode

0 class Solution {

1 public:

2 int minimumOperations(const vector<int> &nums, int start, int goal) const {

3 bool seen[1001] = {0};

4 queue<int> q;

5

6 seen[start] = true;

7 q.emplace(start);

8

9 for (int lvl = 1; !q.empty(); lvl++) {

10 for (int l = size(q); l > 0; l--) {

11 const int crnt = q.front();

12 q.pop();

13

14 for (const int n : nums) {

15 const int x = crnt ^ n;

16 if (x == goal) return lvl;

17 if (x >= 0 && x <= 1000 && !seen[x]) {

18 seen[x] = true;

19 q.emplace(x);

20 }

21

22 const int y = crnt + n;

23 if (y == goal) return lvl;

24 if (y >= 0 && y <= 1000 && !seen[y]) {

25 seen[y] = true;

26 q.emplace(y);

27 }

28

29 const int z = crnt - n;

30 if (z == goal) return lvl;

31 if (z >= 0 && z <= 1000 && !seen[z]) {

32 seen[z] = true;

33 q.emplace(z);

34 }

35 }

36 }

37 }

38

39 return -1;

40 }

41 };