save project

my_search.py

@@ -4,6 +4,24 @@ alist = []
 for i in range(1, 101):
 for i in range(1, 101):
     alist.append(i)
     alist.append(i)
 num = random.choice(alist)
 num = random.choice(alist)
+print( num)
 # 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):
\ No newline at end of file
+    low = 0 
+    hight =len(alist)-1
+    # mid = (low+hight) // 2
+    while hight > low:
+        mid = (low+hight) // 2
+        if alist[mid] == num:
+            return mid 
+        elif alist[mid]<num:
+            low = mid +1
+        else:
+            hight = mid-1
+    return None
+
+
+num = binary_search(alist,num)
+
+print(num)
\ No newline at end of file