diff options
Diffstat (limited to 'most_stones_remove.cpp')
-rw-r--r-- | most_stones_remove.cpp | 47 |
1 files changed, 0 insertions, 47 deletions
diff --git a/most_stones_remove.cpp b/most_stones_remove.cpp deleted file mode 100644 index 97499f8..0000000 --- a/most_stones_remove.cpp +++ /dev/null @@ -1,47 +0,0 @@ -// 947. Most Stones Removed with Same Row or Column -#include "leetcode.h" - -/* - * on a 2d plane, we place 'n' stones at some integer coordinate points. each - * coordinate point may have at most one stone. a stone can be removed if it - * shares either the same row or the same column as another stone that has not - * been removed. given an array 'stones' of length 'n' where 'stones[i] = [x_i, - * y_i]' represents the location of the i'th stone, return the largest possible - * number of stones that can be removed - */ - -class Solution { -public: - int removeStones(vector<vector<int>> &stones) { - int n = stones.size(), c = 0; - unordered_map<int, vector<int>> rows, cols; - for (int i = 0; i < n; ++i) { - rows[stones[i][0]].push_back(i); - cols[stones[i][1]].push_back(i); - } - unordered_set<int> seen; - function<int> dfs; - dfs = [&](int i) -> int { - if (seen.count(i)) - return 0; - seen.insert(i); - int j = stones[i][0], k = stones[i][1]; - for (auto r : rows[j]) - dfs(r); - for (auto c : cols[k]) - dfs(c); - return 1; - }; - for (int i = 0; i < n; ++i) - c += dfs(i); - return n - c; - } -}; - -int main() { - Solution obj; - vvd s1 = {{0, 0}, {0, 1}, {1, 0}, {1, 2}, {2, 1}, {2, 2}}, - s2 = {{0, 1}, {0, 2}, {1, 1}, {2, 0}, {2, 2}}; - printf("%d\n", obj.removeStones(s1)); // expect: 5 - printf("%d\n", obj.removeStones(s2)); // expect: 3 -} |