auto save

diy.py

-with open(r"C:\Users\Administrator\Desktop\新建文本文档.txt","a",encoding="utf-8") as file:
-    file.write("车亿鸣:100本\n")
-    file.write("付晨序:1000本\n")
\ No newline at end of file
+sum=0
+for i in range(1,101):
+    if i%2!=0:
+        sum=sum+i
+    else:
+        sum=sum-i
+print(sum)