save project

my_search.py

@@ -7,4 +7,21 @@ num = random.choice(alist)
 # 请完善二分查找函数binary_search(),查找出num在列表alist里面的索引位置
 
 def binary_search(alist,num):
+    low=0
+    high=len(alist)-1
+    while low<=high:
+        a=(low+high)//2
+        b=alist[a]
+        if b==num:
+            return a
+        elif a>num:
+            high-=1
+        else:
+            high+=1
+    return None
+result=binary_search(alist,num)
+print(num)
+
+
+
     
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