欢迎来到起遇信息学
起遇信息学正处于上线筹建阶段,以下功能已全部开放免费体验: ✅ 完整题库浏览与代码提交评测(C / C++ / Python / Java 等) ✅ 入门到进阶的系列课程试读、作业与考试 ✅ AI 提示、AI 作业分析等智能助教功能 ✅ 赛事模拟与个人能力报告 ✅ 邮箱注册开放 ⏳ 付费课程订阅与微信/支付宝支付通道 ⏳ 手机号登录,微信扫码登录、微信公众号绑定 使用中如遇任何问题,欢迎通过页面底部 **"联系我们"** 与我们沟通。
CF376A.Lever
Lever
You have a description of a lever as string s. We'll represent the string length as record |s|, then the lever looks as a horizontal bar with weights of length |s| - 1 with exactly one pivot. We will assume that the bar is a segment on the Ox axis between points 0 and |s| - 1.
The decoding of the lever description is given below.
- If the i-th character of the string equals "
^", that means that at coordinate i there is the pivot under the bar. - If the i-th character of the string equals "
=", that means that at coordinate i there is nothing lying on the bar. - If the i-th character of the string equals digit c (
1-9), that means that at coordinate i there is a weight of mass c on the bar.
Your task is, given the lever description, print if it will be in balance or not. Assume that the bar doesn't weight anything. Assume that the bar initially is in balance then all weights are simultaneously put on it. After that the bar either tilts to the left, or tilts to the right, or is in balance.
Input
The first line contains the lever description as a non-empty string s (3 ≤ |s| ≤ 106), consisting of digits (1-9) and characters "^" and "=". It is guaranteed that the line contains exactly one character "^". It is guaranteed that the pivot of the lever isn't located in any end of the lever bar.
To solve the problem you may need 64-bit integer numbers. Please, do not forget to use them in your programs.
Output
Print "left" if the given lever tilts to the left, "right" if it tilts to the right and "balance", if it is in balance.
Note
As you solve the problem, you may find the following link useful to better understand how a lever functions: http://en.wikipedia.org/wiki/Lever.
The pictures to the examples:

Samples
=^==
balance
9===^==1
left
2==^7==
right
41^52==
balance
在线编程 IDE
建议全屏模式获得最佳体验
| 进入全屏编程 | Alt+E |
| 递交评测 | Ctrl+Enter |
| 注释/取消注释 | Ctrl+/ |
| 缩放字体 | Ctrl+滚轮 |