save project

my_search.py

 import random
 
 alist = []
-for i in range(1, 101):
+for i in range(1, 101,2):
     alist.append(i)
 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):
\ No newline at end of file
+def binary_search(alist,num):
+    low=0
+    high=len(alist)-1
+    while low<=high:
+        mid=(low+high)//2
+        if alist[mid]==num:
+            return mid
+        elif alist[mid]<num:
+            low=mid+1
+        else:
+            high=mid-1
+    return None
+n=binary_search(alist,num)
+print('给的数',num)
+print('找到位置',n)
\ No newline at end of file