aboutsummaryrefslogtreecommitdiff
path: root/other/most_stones_remove.rs
diff options
context:
space:
mode:
Diffstat (limited to 'other/most_stones_remove.rs')
-rw-r--r--other/most_stones_remove.rs69
1 files changed, 69 insertions, 0 deletions
diff --git a/other/most_stones_remove.rs b/other/most_stones_remove.rs
new file mode 100644
index 0000000..d32137f
--- /dev/null
+++ b/other/most_stones_remove.rs
@@ -0,0 +1,69 @@
+// 947. Most Stones Removed with Same Row or Column
+
+/*
+ * 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
+ */
+
+use std::collections::HashMap;
+struct Solution;
+
+impl Solution {
+ pub fn remove_stones(stones: Vec<Vec<i32>>) -> i32 {
+ let mut ans = 0;
+ let mut parent: Vec<usize> = (0..stones.len()).collect();
+ let mut rows: HashMap<i32, usize> = HashMap::new();
+ let mut cols: HashMap<i32, usize> = HashMap::new();
+ for (i, v) in stones.iter().enumerate() {
+ match rows.get(&v[0]) {
+ Some(&j) => {
+ if Self::union_stone(i, j, &mut parent) {
+ ans += 1;
+ }
+ }
+ None => {
+ rows.insert(v[0], i);
+ }
+ }
+ match cols.get(&v[1]) {
+ Some(&j) => {
+ if Self::union_stone(i, j, &mut parent) {
+ ans += 1;
+ }
+ }
+ None => {
+ cols.insert(v[1], i);
+ }
+ }
+ }
+ ans
+ }
+ fn union_stone(i: usize, j: usize, parent: &mut Vec<usize>) -> bool {
+ let i_root = Self::find_set(i, parent);
+ let j_root = Self::find_set(j, parent);
+ parent[i_root] = j_root;
+ i_root != j_root
+ }
+ fn find_set(x: usize, parent: &mut Vec<usize>) -> usize {
+ if x != parent[x] {
+ parent[x] = Self::find_set(parent[x], parent);
+ }
+ parent[x]
+ }
+}
+
+fn main() {
+ let stones = vec![
+ vec![0, 0],
+ vec![0, 1],
+ vec![1, 0],
+ vec![1, 2],
+ vec![2, 1],
+ vec![2, 2],
+ ];
+ print!("{}", Solution::remove_stones(stones));
+}