save project

binary_search.py

 # 使用二分查找法，找出9和20在列表里面的索引
 # 使用二分查找法，找出9和20在列表里面的索引
-num_list = [1, 3, 5, 8, 11, 15, 17, 18, 20, 21]
+a=18
\ No newline at end of file
+num_list = [1, 3, 5, 8, 11, 15, 17, 18, 20, 21]
+low=0
+best=9
+while low<=best:
+    mid=(best+low)//2
+    guess_num=num_list[mid]
+    if guess_num == a:
+        print("找到了,他在列表里的索引是",mid)
+        break
+    elif guess_num < a:
+        low=mid+1
+    elif guess_num > a:
+        best=mid-1
\ No newline at end of file