Create 1915.Number-of-Wonderful-Substrings.cpp

kazmatw · Jun 28, 2021 · 941984c · 941984c
1 parent 2377226
commit 941984c
Showing 1 changed file with 26 additions and 0 deletions.
diff --git a/Hash/1915.Number-of-Wonderful-Substrings/1915.Number-of-Wonderful-Substrings.cpp b/Hash/1915.Number-of-Wonderful-Substrings/1915.Number-of-Wonderful-Substrings.cpp
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+typedef long long ll;
+class Solution {
+public:
+    long long wonderfulSubstrings(string word) 
+    {
+        int n = word.size();
+        int state = 0;
+        vector<int>count(1<<10);
+        count[0]+=1;
+
+        ll ret = 0;
+        for (int i=0; i<n; i++)
+        {
+            int j = word[i]-'a';
+            state ^= (1<<j);
+
+            ret += count[state];
+
+            for (int j=0; j<10; j++)            
+                ret += count[state ^ (1<<j)];                                
+
+            count[state]++;
+        }
+        return ret;
+    }
+};