Create making-file-names-unique.cpp

Author: kamyu104

C++/making-file-names-unique.cpp

@@ -0,0 +1,22 @@
+// Time:  O(n)
+// Space: O(n)
+
+class Solution {
+public:
+    vector<string> getFolderNames(vector<string>& names) {
+        unordered_map<string, int> count;
+        vector<string> result;
+        unordered_set<string> lookup;
+        for (const auto& name : names) {
+            auto& c = count[name];
+            string name_with_suffix;
+            do {
+                name_with_suffix = c ? name + "(" + to_string(c) + ")" : name;
+                ++c;
+            } while (lookup.count(name_with_suffix));
+            result.emplace_back(name_with_suffix);
+            lookup.emplace(move(name_with_suffix));
+        }
+        return result;
+    }
+};