save project

my_search.py

@@ -7,3 +7,17 @@ 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:
+        mid=(low+high)//2
+        if num == alist[mid]:
+            return num
+        elif num < alist[mid]:
+            high=mid-1
+        else:
+            low=mid+1
+    return "no answer!"
+
+
+print(binary_search(alist,num))
\ No newline at end of file