save project

dip.4

+bingo_num = 20
+num_list = [1,3,5,8,11,15,17,18,20,21]
+low = 0
+high = len(num_list)-1
+while low <= high:
+    mid = (low + high)//2
+    guess_num = num_list[mig]
+    if guess_num == bingo_num:
+        print("找到了，它在列表里的索引是：",mid)
+        break
+    elif guess_num < bingo_num:
+        low = mid + 1
+    elif guess_num > bingo_num:
+        high = mid - 1
+

my_search.py

@@ -7,3 +7,20 @@ 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
 # 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):
+    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
+        else:
+            high = mid - 1
+    return None
+
+
+result = binary_search(alist,num)
+print("老师给的数是：",num)
+print("找到了，它在列表里的索引是：",result)
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