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]
\ No newline at end of file
+num_list = [1, 3, 5, 8, 11, 15, 17, 18, 20, 21]
+num = 20
+high = len(num_list) - 1
+low = 0
+while high > low :
+    mid = ( low + high ) // 2
+    if num_list[mid] == num:
+        print('找到了，索引是' + str(mid))
+        break
+    elif num_list[mid] > num:
+        high = mid - 1
+    else :
+        low = mid + 1 
+if high <= low:
+    print('没找到')