Create 22 noMatchingSubseq.cpp

June Leetcode Challenge 2021/22 noMatchingSubseq.cpp

@@ -0,0 +1,29 @@
+struct Node {
+ string word;
+ int index;
+ Node(const string &word, int index) : word(word), index(index) {}
+};
+class Solution {
+public:
+ int numMatchingSubseq(string s, vector<string>& words) {
+ unordered_map<char, vector<Node>> buckets;
+ for (string& word : words) {
+ char startingChar = word[0];
+ buckets[startingChar].push_back(Node(word, 0));
+ }
+ int ans = 0;
+ for (char c : s) {
+ auto currBucket = buckets[c];
+ buckets[c] = {};
+ for (Node& node : currBucket) {
+ node.index += 1; // Point to next character of node.word
+ if (node.index == node.word.size()) {
+ ans += 1;
+ } else {
+ buckets[node.word[node.index]].push_back(node);
+ }
+ }
+ }
+ return ans;
+ }
+};