save project

my_search.py

@@ -5,5 +5,21 @@ 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 binary_search(alist,num):
 def binary_search(alist,num):
+    low=0 
+    high=len(alist)-1
+    while high>=low:
+        mid=(low+high)//2
+        guess=alist[mid]
+        if guess==num:
+            return mid
+        elif guess<num:
+            low=mid+1
+        else:
+            high=mid-1
+a=binary_search(alist,num)
+print(a)
+
+        
+
+