Create count-the-number-of-consistent-strings.cpp

Author: kamyu104

C++/count-the-number-of-consistent-strings.cpp

@@ -0,0 +1,22 @@
+// Time:  O(n)
+// Space: O(1)
+
+class Solution {
+public:
+    int countConsistentStrings(string allowed, vector<string>& words) {
+        int result = size(words);
+        vector<bool> lookup(26);
+        for (const auto& c: allowed) {
+            lookup[c - 'a'] = true;
+        }
+        for (const auto& word: words) {
+            for (const auto& c: word) {
+                if (!lookup[c - 'a']) {
+                    --result;
+                    break;
+                }
+            }
+        }
+        return result;
+    }
+};