Given a non-empty string, encode the string such that its encoded length is the shortest. The encoding rule is: k[encoded_string], where the encoded_string inside the square brackets is being repeated exactly k times. Note: k will be a positive integ
运算符 1.算数运算: 2.比较运算: 3.赋值运算: 4.逻辑运算: 5.成员运算: name = "yehaoran " # in 判断ye是否在name里面 在的话返回ok 不在返回not # if "ye" in name : # print("ok") # else: # print("not") if "ran" not in name: print("ok") else:
推导式分为列表推导式(list),字典推导式(dict),集合推导式(set)三种 1.列表推导式也叫列表解析式.功能:是提供一种方便的列表创建方法,所以,列表解析式返回的是一个列表格式:用中括号括起来,中间用for语句,后面跟if语句用作判读,满足条件的传到for语句前面用作构建先的列表 [x**2 for item in item_list if item>2] 例子: >>> li=[i*2 for i in range(10) if i % 2 == 0] >>