auto save

1.py

+tianshu=int(input("天数:"))
+num=0
+for i in range(1,tianshu+1):
+    num+=i
+print(num)
\ No newline at end of file

3.py

+a=int(input(":"))
+list=[]
+b=0
+c=0
+for i in range(1,a+1):
+    list.append(i)
+while True:
+    if len(list)==1:
+        break
+    else:
+        b+=1
+        c=list[0]
+        list.pop(0)
+        if b==3:
+            b=0
+            continue
+        else:
+            list.append(c)
+print(list)
\ No newline at end of file