From f19cc7af82eb9cd0766e5905c942004fa17f3c70 Mon Sep 17 00:00:00 2001
From: chayan das <110921638+Chayandas07@users.noreply.github.com>
Date: Wed, 25 Sep 2024 23:42:56 +0530
Subject: [PATCH] Create 2416. Sum of Prefix Scores of Strings

---
 2416. Sum of Prefix Scores of Strings | 56 +++++++++++++++++++++++++++
 1 file changed, 56 insertions(+)
 create mode 100644 2416. Sum of Prefix Scores of Strings

diff --git a/2416. Sum of Prefix Scores of Strings b/2416. Sum of Prefix Scores of Strings
new file mode 100644
index 0000000..d04ed8f
--- /dev/null
+++ b/2416. Sum of Prefix Scores of Strings	
@@ -0,0 +1,56 @@
+// Trie Node definition
+class trie {
+    public:
+        int x;  // To store how many times the prefix ending at this node has been seen.
+        trie *v[26];  // Array of pointers to children nodes for each character 'a' to 'z'.
+};
+
+// Function to insert a string into the Trie and update prefix counts
+void maketrie(string str, trie* node) {
+    for (auto &i: str) {  // Traverse each character in the string
+        // If the node for this character doesn't exist, create it
+        if (node->v[i - 'a'] == NULL) {
+            node->v[i - 'a'] = new trie();  // Create a new Trie node
+            node = node->v[i - 'a'];  // Move to the newly created node
+            node->x = node->x + 1;  // Increment the count for this prefix
+        } else {
+            node = node->v[i - 'a'];  // Move to the existing node
+            node->x = node->x + 1;  // Increment the count for this prefix
+        }
+    }
+}
+
+// Function to calculate the sum of prefix scores for a given string
+void solve(string str, trie* node, int &x) {
+    trie* p = node;  // Pointer to traverse the Trie
+    for (auto &i: str) {  // Traverse each character in the string
+        p = p->v[i - 'a'];  // Move to the next node in the Trie
+        x += p->x;  // Add the count of this prefix to the total score
+    }
+}
+
+// Main solution class
+class Solution {
+public:
+    // Function to calculate sum of prefix scores for all words
+    vector<int> sumPrefixScores(vector<string>& words) {
+        trie *node = new trie();  // Create the root node of the Trie
+        
+        // Step 1: Insert each word into the Trie and build the prefix tree
+        for (auto &i: words) {
+            maketrie(i, node);  // Insert word into the Trie
+        }
+        
+        vector<int> ans;  // Vector to store the final prefix scores
+        int x = 0;  // Variable to store the current score for a word
+        
+        // Step 2: Calculate the prefix score for each word
+        for (auto &i: words) {
+            x = 0;  // Reset the score for the new word
+            solve(i, node, x);  // Calculate the prefix score for the current word
+            ans.push_back(x);  // Store the score in the answer vector
+        }
+        
+        return ans;  // Return the final list of prefix scores
+    }
+};