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
-high=len(num_list)-1
-num=20
-while low<=high:
+
+def binary_search(num_list,num):
+    low=0
+    high=len(num_list)-1
+    while low<=high:
         mid=(low+high)//2
         mid=(low+high)//2
         s=num_list[mid]
         s=num_list[mid]
         if s<num:
         if s<num:
@@ -11,6 +12,6 @@ while low<=high:
         if s>num:
         if s>num:
             high=mid-1
             high=mid-1
         if s==num:
         if s==num:
-        print(mid)
-        break
-
+            return mid
+a=binary_search(num_list,17)
+print(a)