diff --git a/17-240525-pass/main.py b/17-240525-pass/main.py
new file mode 100644
index 0000000..e2dd0af
--- /dev/null
+++ b/17-240525-pass/main.py
@@ -0,0 +1,30 @@
+class Solution:
+    def letterCombinations(self, digits: str) -> List[str]:
+        m = {
+            1: '',
+            2: 'abc',
+            3: 'def',
+            4: 'ghi',
+            5: 'jkl',
+            6: 'mno',
+            7: 'pqrs',
+            8: 'tuv',
+            9: 'wxyz',
+        }
+        rlt = []
+        for ch in digits:
+            num = int(ch)
+            if len(rlt) == 0:
+                for l in m[num]:
+                    rlt.append(l)
+            else:
+                tmp_rlt = rlt.copy()
+                for length in range(len(m[num])):
+                    ch = m[num][length]
+                    if length == 0:
+                        for index, s in enumerate(rlt):
+                            rlt[index] = tmp_rlt[index] + ch
+                    else:
+                        for index, s in enumerate(tmp_rlt):
+                            rlt.append(tmp_rlt[index] + ch)                            
+        return rlt
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