save project

binary_search.py

 # 使用二分查找法，找出9和20在列表里面的索引
 # 使用二分查找法，找出9和20在列表里面的索引
-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[mid]
-    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
+import random
+alist = []
+for i in range(1,101):
+    alist.append(i)
+num = random.choice(alist)
+def binary_search(alist,num):
+    low = 0
+    high = len(alist)-1
+    while low<= high:
+        mid = (low + high)//2
+        guess = alist[mid]
+        if guess ==num:
+            rsturn mid
+        elif guess < num:
+            low = mid+1
+        else:
+            high = mid-1
+        return None
+result = binary_search(alist,num)
+print("",num)
+print("",result)