aboutsummaryrefslogtreecommitdiff
path: root/sum_dist_tree.rs
diff options
context:
space:
mode:
Diffstat (limited to 'sum_dist_tree.rs')
-rw-r--r--sum_dist_tree.rs49
1 files changed, 49 insertions, 0 deletions
diff --git a/sum_dist_tree.rs b/sum_dist_tree.rs
new file mode 100644
index 0000000..d000d83
--- /dev/null
+++ b/sum_dist_tree.rs
@@ -0,0 +1,49 @@
+struct Solution;
+
+impl Solution {
+ pub fn sum_of_distances_in_tree(n: i32, edges: Vec<Vec<i32>>) -> Vec<i32> {
+ let n = n as usize;
+ let mut adj: Vec<Vec<usize>> = vec![Vec::new(); n];
+ for e in edges.iter() {
+ adj[e[0] as usize].push(e[1] as usize);
+ adj[e[1] as usize].push(e[0] as usize);
+ }
+ let mut dp = vec![[0; 2]; n];
+ Self::get_depth_sum_count(0, n, &mut dp, &adj);
+ let mut ans = vec![0; n];
+ Self::get_ans(0, n, 0, &mut ans, &dp, &adj);
+ ans
+ }
+ fn get_depth_sum_count(i: usize, parent: usize, dp: &mut Vec<[i32; 2]>, adj: &Vec<Vec<usize>>) {
+ dp[i][1] = 1;
+ for &j in adj[i].iter() {
+ if j == parent {
+ continue;
+ }
+ Self::get_depth_sum_count(j, i, dp, adj);
+ dp[i][0] += dp[j][0] + dp[j][1];
+ dp[i][1] += dp[j][1];
+ }
+ }
+ fn get_ans(i: usize, parent: usize, acc_sum: i32, ans: &mut Vec<i32>, dp: &Vec<[i32; 2]>, adj: &Vec<Vec<usize>>) {
+ ans[i] = acc_sum + dp[i][0];
+ for &j in adj[i].iter() {
+ if j == parent {
+ continue;
+ }
+ let sum2 = acc_sum + dp[i][0] + dp.len() as i32 - dp[j][0] - dp[j][1] * 2;
+ Self::get_ans(j, i, sum2, ans, dp, adj);
+ }
+ }
+}
+
+fn main() {
+ let edges = vec![
+ vec![0,1],
+ vec![0,2],
+ vec![2,3],
+ vec![2,4],
+ vec![2,5]
+ ];
+ print!("{:?}", Solution::sum_of_distances_in_tree(6, edges));
+}