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
 num_list = [1, 3, 5, 8, 11, 15, 17, 18, 20, 21]
-low=0
-high=len(num_list)-1
 
-guess=21
-while low<=high :
-    mid=(low+high)//2
-    num=num_list[mid]
-    if guess==num:
-        print('找到了'+str(guess)+"索引位是：",mid)
-        break
-    elif guess<num:
-        high=mid-1
-    else:
-        low= mid+1
 
-guess=9
-while low<=high :
-    mid=(low+high)//2
-    num=num_list[mid]
-    if guess==num:
-        print('找到了'+str(guess)+"索引位是：",mid)
-        break
-    elif guess<num:
-        high=mid-1
-    else:
-        low= mid+1
\ No newline at end of file
+def bs(alist,num):
+    low=0
+    high=len(alist)-1
+    guess=21
+    while low<=high :
+        mid=(low+high)//2
+        num=alist[mid]
+        if guess==num:
+            print('找到了'+str(guess)+"索引位是：",mid)
+            break
+        elif guess<num:
+            high=mid-1
+        else:
+            low= mid+1
+result=bs(num_list,21)
+print(result)