50 lines
1.3 KiB
C#
50 lines
1.3 KiB
C#
public class Solution {
|
|
private class Node {
|
|
public Dictionary<char, Node> Next { get; set; } = new();
|
|
public bool Has { get; set; } = false;
|
|
|
|
public Node() { }
|
|
}
|
|
|
|
private static Node MakeTrie(string[] dictionary) {
|
|
var root = new Node();
|
|
|
|
foreach (var word in dictionary) {
|
|
var node = root;
|
|
foreach (var c in word) {
|
|
if (!node.Next.ContainsKey(c)) {
|
|
node.Next[c] = new();
|
|
}
|
|
node = node.Next[c];
|
|
}
|
|
node.Has = true;
|
|
}
|
|
|
|
return root;
|
|
}
|
|
|
|
public int MinExtraChar(string s, string[] dictionary) {
|
|
var trie = MakeTrie(dictionary);
|
|
|
|
var length = s.Length;
|
|
var dp = new int[length + 1];
|
|
|
|
for (var start = length - 1; start >= 0; --start) {
|
|
dp[start] = 1 + dp[start + 1];
|
|
|
|
var node = trie;
|
|
for (var end = start; end < length; ++end) {
|
|
if (!node.Next.ContainsKey(s[end])) {
|
|
break;
|
|
}
|
|
|
|
node = node.Next[s[end]];
|
|
if (node.Has) {
|
|
dp[start] = Math.Min(dp[start], dp[end + 1]);
|
|
}
|
|
}
|
|
}
|
|
|
|
return dp[0];
|
|
}
|
|
}
|