save project

my_search.py

@@ -3,7 +3,22 @@ import random
 alist = []
 for i in range(1, 101):
     alist.append(i)
-num = random.choice(alist)
+n = 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
+        g = alist[m]
+        if g == n:
+            return m
+        elif g < n:
+            l = m + 1
+        else:
+            h = m - 1
+    return None
+result = binary_search(alist,n)
+print("老师给的数是：",n)
+print("它在列表里的索引是：",result)
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