save project

my_search.py

@@ -5,5 +5,24 @@ for i in range(1, 101):
     alist.append(i)
     alist.append(i)
 num = random.choice(alist)
 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
 # 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 
-def binary_search(alist,num):
+
+def binary_search(alist,num):
\ No newline at end of file
+    low=0
+    high=len(alist)-1
+
+
+    while low<=high:
+        mid=(low+high)//2
+        guess=alist[mid]
+        if guess==num:
+            print('找到了，是',mid)
+            
+
+        elif guess<num:
+            low=mid+1
+        else:
+            high+mid-1
+    return None
+a=binary_search(alist,num)
+print(num)
+