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]
 num_list = [1, 3, 5, 8, 11, 15, 17, 18, 20, 21]
 low=0
 low=0
-high=len(num_len)-1
-mid=(low+high)//2
+high=len(num_list)-1
+
 while True:
 while True:
+    mid=(low+high)//2
     if num_list[mid]==20:
     if num_list[mid]==20:
         print('找到了')
         print('找到了')
+        print(mid)
         break
         break
-    elif:
-        num_list[mid]<20:
+    elif num_list[mid]<20:
+        
         low=mid+1
         low=mid+1
     else:
     else:
         high=mid-1
         high=mid-1
+    if high<low:
+        print('无')
+        break
+
         
         
+
+