15

JavaProgrammerLB · JavaProgrammerLB · commit 110ec2ad6126 · 2017-11-21T20:11:59.000+08:00
diff --git a/15.py b/15.py
@@ -1,31 +1,14 @@
-import datetime
+from calendar import isleap
+from datetime import date
+
 
 def main():
-    for i in range(100):
-        s = "1"
-        if i < 10:
-            s += "0"
-        s += str(i)
-        s += "6"
-        year = int(s)
-        if leap(year):
-            d = datetime.datetime(year, 1, 27).strftime("%w")
-            if d == "2":
-                print(year)
+    Tuesday = 1
+    for year in range(1006, 1997, 10):
+        d = date(year, 1, 27)
+        if isleap(year) and d.weekday() == Tuesday:
+            print(d)
 
-def leap(year):
-    result = False
-    if year % 4 == 0:
-        if year % 100 == 0:
-            if year % 400 == 0:
-                result = True
-            else:
-                result = False
-        else :
-            result = True
-    else:
-        result = False
-    return result
 
 if __name__ == "__main__":
     main()
diff --git a/README.md b/README.md
@@ -1,6 +1,20 @@
 # pythonchallenge
 Solve Problems in http://www.pythonchallenge.com
 
+#### 15
+result: http://www.pythonchallenge.com/pc/return/mozart.html
+
+```python
+from calendar import isleap
+from datetime import date
+```
+
+- year 1756 is a leap year
+- 1756-1-27 is Tursday
+- mozart's birthday is 1756-1-27
+- mozart is the second youngest boy in his family
+
+
 #### 14
 result: http://www.pythonchallenge.com/pc/return/uzi.html
 ```
