save project

my_search.py

@@ -4,6 +4,20 @@ 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)
-# 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 c(alist,num):
\ No newline at end of file
+    low = 0
+    high = len(alist)-1
+    while low <=high:
+        mid = (low + high)//2
+        guess = alist[mid]
+        if guess==num:
+            return mid
+        elif guess<num:
+            low=mid+1
+        elif guess>num:
+            high=mid-1
+    return None
+a=c(alist,num)
+print(num)
+print(a)
\ No newline at end of file