save project

my_search.py

@@ -6,4 +6,18 @@ for i in range(1, 101):
 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):
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+def binary_search(alist,num):
+    l = 0
+    h = len(alist)-1
+    while l <= h:
+        m = (l + h) // 2
+        guess = alist[mid]
+        if guess == num:
+            return mid
+        elif guess < num:
+            l = m + 1
+        else:
+            h = m - 1
+    return None
+r = binary_search(num,list,2)
+print(r)
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