diff --git a/Letter Combinations of a Phone Number b/Letter Combinations of a Phone Number
new file mode 100644
index 0000000..fe1334a
--- /dev/null
+++ b/Letter Combinations of a Phone Number	
@@ -0,0 +1,24 @@
+class Solution {
+public:
+    const vector<string> pad = {
+        "", "", "abc", "def", "ghi", "jkl",
+        "mno", "pqrs", "tuv", "wxyz"
+    };
+    
+    vector<string> letterCombinations(string digits) {
+        if (digits.empty()) return {};
+		vector<string> result;
+        result.push_back("");
+        
+        for(auto digit: digits) {
+            vector<string> tmp;
+            for(auto candidate: pad[digit - '0']) {
+                for(auto s: result) {
+                    tmp.push_back(s + candidate);
+                }
+            }
+            result.swap(tmp);
+        }
+        return result;
+    }
+};